Easy (5 Minute) DIY Vitamin C Serum Recipe

Affiliate Disclosure: I receive a small commission for purchases made via affiliate links.
How to cite: Wong M. Easy (5 Minute) DIY Vitamin C Serum Recipe. Lab Muffin Beauty Science. December 10, 2022. Accessed March 19, 2024. https://labmuffin.com/easy-5-minute-diy-vitamin-c-serum-recipe/

I’ve mentioned my super-easy DIY vitamin C serum a few times before on social media, and some of you have been asking me for the recipe… but I’ve been so distracted with other things I never got around to posting it until now.

I’m sorry! Please forgive me. I hope the results make up for my tardiness!

Here’s the video (you may need to disable AdBlock to see it) – scroll down for the recipe. Click here to watch on YouTube.

 

What Does Vitamin C Do in Skincare?

Vitamin C is a superstar anti-aging ingredient in skincare. It tackles anti-aging on lots of levels:

  • Can increase collagen, which plumps up skin and decreases wrinkles
  • Fades hyperpigmentation (brown marks like acne scars and sun spots)
  • Acts as an antioxidant, protecting against free radical damage from UV, pollution and natural aging

Who wouldn’t want this, right? It does a bit of everything!

Related post: Antioxidants in Skincare: What Do They Do?

The Problem With Vitamin C

The big problem with using vitamin C in products is that L-ascorbic acid is very unstable in water-based products. It turns into yellow dehydroascorbic acid (DHA or DHAA) and other products quickly. In one study at pH 3.52 and 25 °C in amber glass, 50% is gone in a week.

Luckily, DHA can convert back to L-ascorbic acid, and there’s no evidence that it’s bad for your skin (there’s actually a product with an accompanying non-peer-reviewed study that actually uses it as a way of getting vitamin C into your skin more easily). But there’s not a lot of evidence that it’s as beneficial either either, and it degrades further into products that can’t be turned back into L-ascorbic acid.

Related post: Why Vitamin C Can Stain Your Skin (and How to Avoid It!)

It’s well-documented that L-ascorbic acid can be stabilised by combining it with vitamin E and ferulic acid (plus it makes it work better). This is the approach used in serums from SkinCeuticals, Paula’s Choice, Timeless, Geek & Gorgeous, Maelove and Ausceuticals. However, if you want to DIY with this combo, it not only requires buying vitamin E and ferulic acid, but you’ll also have to get an emulsifier because vitamin E doesn’t play nicely with water.

And if you’ve gone to the trouble of mixing all that, you’ll also want a preservative to suppress bacterial growth so it’ll last longer, and you won’t have to remake it any time soon.

Related post: Ultimate Vitamin C Skincare Guide Part 1: Ascorbic Acid (with video)

The price of all these ingredients adds up quickly, and if you’ve done any DIY before, you’ll know that you’ll end up with barely-used bottles of ingredients that will go off before you finish them.

L-Ascorbic acid can also be stabilised by altering its chemical structure. Some derivatives of LAA include magnesium ascorbyl phosphate (MAP), ascorbyl glucoside and ascorbyl tetraisopalmitate (ATIP)/tetrahexyldecyl ascorbate (THDA). However, these are expensive compared to LAA, and they need to be converted back into LAA to work as effectively.

Related post: Mythbusting: Are Vitamin C Serums Bad for You?

The Solution: DIY Vitamin C Serum

Easy (5 Minute) DIY Vitamin C Serum

All these issues can be solved by using a DIY vitamin C serum that you remake every week or so.

I generally find DIY a bit of a pain – the minimum orders of the ingredients are too large for me to use up personally so I end up spending way more money than using a pre-made product. And there’s the horrible feeling of wastage when you chuck out expired, barely-used ingredients.

There’s also the time required to cook up your product, the failed batches, and the dreaded washing-up afterwards. But this DIY serum has a lot of upsides:

  • All the ingredients and materials are easy to get and inexpensive
  • It takes about 5 minutes to make with no special equipment required
  • It can be more effective than many store-bought products – you don’t have to deal with delivery times and distribution networks, or having your vitamin C sit on a store shelf slowly degrading for an unknown period of time
  • You can easily adjust the amount of vitamin C in your serum – add more LAA to ramp up the effectiveness, or use less LAA to decrease irritation
  • It’s cheap enough that I don’t feel bad slapping it all over my face, chest and body

The downsides:

  • Time and effort to make and remake it
  • There are no supporting ingredients in the formula to make the LAA more effective, like penetration enhancers (aside from the low pH) or antioxidants which could replenish oxidised LAA on the skin
  • There are no soothing ingredients to reduce any irritation – you can make it more gentle with a lower %, higher pH or by layering another product
  • Some basic equipment required
  • Some (low) risk of microbial contamination. The hydronium ions from the low pH act as the preservative for the short amount of time you’ll be using it, and the simple formula doesn’t contain much nutrition for microbes. But the longer you keep using it, the higher the risk gets.
  • Risk of messing up the procedure – while it’s very simple, there’s always the possibility that some people will make it wrong. If you mess up recipes for food a lot, this might not be for you – do this at your own risk!

For a formula this simple, you’re best off sticking to the generally accepted conditions for effective ascorbic acid delivery into the skin: 5 to 20% LAA, at a pH less than 3.5. At higher concentrations, the effectiveness of LAA doesn’t seem to increase too much, but the side effects (mostly irritation) likely will.

Easy DIY Vitamin C Serum Recipe

Ingredients and Materials

Here’s what you need for a super basic serum:

Easy DIY Vitamin C Serum

1. L-Ascorbic acid powder

As a dry solid, LAA is reasonably stable and cheap. You can find it at most supplement stores, or you can order it off iHerb like I did (Amazon has this brand too).

Some powders apparently don’t dissolve very well, but I didn’t have any issues with NutriBiotic. NOW Foods is slightly cheaper, but I don’t know how easily it dissolves. I don’t recommend using crushed tablets because it ends up more expensive, plus you end up with random bits of fillers on your face.

2. Distilled water

Metal ions in your water can speed up the rate of LAA decomposition, especially since there’s nothing else in the formula stabilising it. You can get distilled or deionised water at the supermarket for a few dollars.

You can also use water filtered through a very fine filter that can remove metal ions (a nanofilter). Alternatively, you can use tap water and just remake your serum more frequently.

3. Baking soda (sodium bicarbonate)

The pH of ascorbic acid alone in water is going to be too low (too acidic), which will cause unnecessary irritation. Baking soda is alkaline, so we can use it to adjust the pH back up, closer to skin pH. 

Note: This is not the same as baking powder! Baking soda (sodium bicarbonate) is a single substance, which behaves much more predictably.

4. pH strips

To see what the pH is. It doesn’t have to be exact, so any indicator strips will do – I prefer the four-square indicator strips from Merck so I don’t second-guess my colour matching abilities. You can get similar ones here.

5. 1/4 teaspoon measuring spoon

1/4 teaspoon is 1.23 or 1.48 mL (depending if it’s US or Imperial), which translates to ~1 g ascorbic acid. Ideally weighing it is much more accurate, but for this quick-and-dirty recipe volumetric measurement will do. I would recommend not aiming near the top of the % range, to give some leeway each way if the mass-to-volume conversion is off.

6. A suitable container

You want an airtight(-ish) clean container. It doesn’t have to be truly airtight since you’ll be remaking this often. 

I originally made this serum with a spray bottle, but over time I found that the spring inside started to rust. I’d recommend a bottle with largely glass or rubber components such as a dropper bottle or an essential oil bottle.

7. Aluminium foil

Enough to wrap around your container to lightproof it. Even if your container has coloured glass, this is a good idea!

Note: I’ve since run my own experiments and found that this doesn’t seem to make a huge difference.

Directions

Step 1

Work out how much serum you can fit into your container in millilitres.

If it’s new or a product container you’re reusing, it should say on the packaging. If you can’t work it out, you can either check how many teaspoons of water fit in it using a teaspoon measure, or eyeball it against similar containers you own.

Step 2

Calculate how many grams of LAA you need.

  • For a 5% serum, multiply the volume of your container in mL by 0.05 to get the LAA required in grams. (grams = mL x 0.05)
  • For a 10% serum, multiply the volume of your container by 0.1 to get the LAA required in grams. (grams = mL x 0.1)
  • For a 20% serum, multiply the volume of your container by 0.2 to get the LAA required in grams. (grams = mL x 0.2)

For example, I’m making 20 mL of a 10% vitamin C serum: grams = 20 x 0.1 = 2 grams LAA.

Step 3

Clean your container.

Wash it out thoroughly then rinse with alcohol (methylated spirits) and let dry, then rinse it out a few times with your distilled water. If you don’t have time for this, you can skip the alcohol but it could lead to it going off faster (if you remake it weekly it shouldn’t be a problem).

Step 4

Put the appropriate amount of LAA into your container.

If you have scales capable of weighing to the nearest 0.1 g, you can use them (best approach).

A faster and reasonably accurate method is to use your 1/4 teaspoon measure and assume that a level teaspoon is approximately 1.5 g. It doesn’t have to be super exact – your skin isn’t going to respond significantly differently to 5% ascorbic acid vs 7% ascorbic acid. Again, it’s best not to go too high or low with the % so you have some leeway each way if the mass-to-volume conversion isn’t exactly that.

(If you’re super diligent and own scales, you can calibrate your teaspoon and your particular ascorbic acid powder by weighing out a flat teaspoon yourself, then using the faster teaspoon measure for future batches.)

Step 5

Dissolve the LAA powder.

Add about half the distilled water, put the lid on and give it a healthy shake until all the LAA powder has dissolved. If you fill the bottle all the way to the top, it’s harder to shake.

Easy DIY Vitamin C Serum

Step 6

Add the rest of the water. Shake a few times until it’s mixed.

Step 7

Adjust the pH.

Put a drop of serum on your pH strip to check the pH (you can dip the strip in if you want, but you might end up with ugly floaty bits in your serum). It’s probably going to be too low. Add baking soda a tiny bit at a time, testing the pH as you go, until the pH is between 3 and 4.

Easy DIY Vitamin C Serum

As an indication, for 20 mL of my 10% serum, I found that I needed about 3 rice grains’ worth of baking soda to get to pH ~3.5. Your amount will likely be different, since baking soda gets weaker with exposure to carbon dioxide in the air.

Step 8

Wrap the bottle in foil. This is a little trick I picked up in the lab during my PhD. It’s the easiest and cheapest way to protect a light-sensitive substance.

Note: Since I first wrote this post, I’ve done some experiments and it seems like foil doesn’t make a big difference.

Easy DIY Vitamin C Serum

How long does this DIY vitamin C serum last?

With light protection, I’ve found that it gets slightly yellow after a week, and noticeably yellow after 2 weeks, so I think 2 weeks is the upper limit here. The pH is low enough that most microbes won’t be able to thrive so microbial growth isn’t a big worry, especially when you won’t be keeping the serum for very long.

Once you’re used to the process, I reckon you’ll be able to make it in under 5 minutes! (I’m curious about how quickly this can be done, so if you decide to time yourself please let me know! I’ll update with the time I take for my next batch.)

Questions about this recipe

In the few years I’ve had this recipe up, I’ve had a bunch of questions about whether or not it’ll really work, if it’s dangerous etc. – so here they are in the one spot.

Why doesn’t DIY vitamin C serum need preservatives?

In DIY communities, the usual mantra is that all water-based products need added preservatives… which isn’t quite accurate. Low pH, or high hydrogen/hydronium ion concentrations, is in itself a preservative. For example, vinegar is self-preserving, and can be used to preserve other foods.

In general, products with a pH below 4 or above 10 (i.e. 1000 times more acidic or basic than water) won’t need a preservative.

Of course, extreme pH doesn’t work for a lot of formulations like emulsions. But this only has an aqueous phase (it’s a homogeneous solution).

On top of this, it’s a very simple, low-risk formula without any ingredients that act as good nutrition for microbes. (This may change if you add any other ingredients to it.)

There’s also the fact we’re only keeping this product for less than a few weeks before throwing it out, so the low pH should be sufficient to keep this simple formula preserved for that length of time.

Won’t the L-ascorbic acid crystallise on your skin and not work?

I’ve seen some people say that L-ascorbic acid from this serum will crystallise on your skin and not penetrate because there aren’t any other solvents in this product (e.g. glycols) to keep it dissolved.

However, there’s evidence that products containing solid L-ascorbic acid will work fine on skin. For example, this study found increased collagen and cytokeratin when a water-free product containing microfine ascorbic acid crystals was applied to skin samples. It’s likely that water evaporating from your skin (through TEWL) will gradually dissolve any ascorbic acid on your skin and allow it to absorb.

Isn’t it dangerous to measure by volume using a teaspoon instead of weighing the ascorbic acid properly?

It’s definitely better to weigh out the ascorbic acid. However, there’s a pretty big leeway in how much ascorbic acid can be used in vitamin C serums, so if you aim for a 10% serum, you can be out by a factor of 2 each way and still end up at 5-20%.

Plus there’s also the fact that the main risk with this serum is low pH. However, we adjust and test the pH after the ascorbic acid’s been added, which means the volumetric measuring has no effect on this aspect.

Don’t you need to use cosmetic grade ascorbic acid?

Pharmaceutical grade ascorbic acid is generally purer than cosmetic grade ascorbic acid, and cosmetic formulations often use pharna grade LAA.

Since L-ascorbic acid is a pure compound, there isn’t much variation in composition. It’s possible that cosmetic grade ascorbic acid might dissolve more easily, but you can grind up the ascorbic acid to help it along, or wait a few more minutes for it to dissolve.

Easy DIY vitamin C serum

 

This post contains affiliate links – if you decide to click through and support Lab Muffin financially (at no extra cost to you), thank you! For more information, see Disclosure Policy.


Skincare Guide


Related Posts

242 thoughts on “Easy (5 Minute) DIY Vitamin C Serum Recipe”

      • Hi Michelle! Won’t the pH adjustment with sodium bicarbonate neutralise a lot of vitamin C – meaning it will turn those two -OH groups into their oxidised =O forms?

        Reply
        • The sodium bicarbonate will help raise the pH to match the pH of your skin (around 3.5). The serum will still be acidic (plenty of H+ ions) and will not completely neutralize at this pH. Therefore, plenty of active vitamin C present in the serum. Remember, you are simply adjusting the pH to about 3.5…not 7, which would be a complete neutralization reaction.

          Reply
        • Thank you for your informed advice . I make vitamin c serum every few days and am much more comfortable with a volumetric form of measurement. Would it be correct to say that for 20 % strength for a 20 ml bottle the ratio would be: 4 teaspoons of water to 1 teaspoon of ascorbic acid?
          Also, I use aloe Vera in place of distilled water is that alright and add a drop or 2 of glycerine. I see now the importance of the ph and just ordered those strips.
          Thank you!

          Reply
        • Thanks so much for this!

          Made this in the 10% and I used digital scales (precise to 1g but countered this by doing it multiple times over and making it close to the 1/4 tsp). I only eyeballed the baking soda part and I think this is where I messed up- do you mean 3 grains of rice in volume, or 3 grains of rice in weight? And what kind of grain of rice- short, long, white, brown?

          Could you give us an exact measurement in grams or percentage of my 1/4 teaspoon measurement. (I’m too poor for pH strips haha)

          I put it on my face and it itched and felt irritated. I don’t ever have any immediate reactions to skincare so I assume it was due to the acidity. While still wet though, I put on some moisturizer to dilute it, and it calmed the irritation down.

          Reply
      • I recently bought vitamin c powder from the ordinary plus their Resveratrol 3% + Ferulic Acid 3%. Every night I take a 1/4 teaspoon of the powder with a few drops of the serum and rub on my face. Do you see any problem with that ? I have no idea what the strength is but the application is simple enough. I did peel at first but not any more. Thanks

        Reply
      • I followed you serum 5 min directions. It was super easy.
        I did have to add a couple pinches of backing soda. My acid was super acidic. My only issue i had was the vit. C did NOT dissolve. I shook all day. Lol

        I then remembered that I had ferulic acid. It just put a couple pinches in. I had not a clue which way to go as to measuring. Are you able to help me on the ferulic acid amount as well??

        Even with the ferulic. The serum came to 3.42, which I thought was perfect.

        At the end of the day.. how the heck am I going to get the grit to dissolve. I used both 1TSP of distilled and a little more that 1/2 TSP of glycerin. It soaked into my skin nicely. But there are a couple spots were it feels a little sandy.

        Thanks for your video.

        Reply
        • Hi there, I read this and thought, what if you crush the vit c with a pestle n mortar? would that help maybe ?

          Reply
      • I can’t really say – glycerin can increase microbial growth so I would recommend avoiding it if you want to keep it for a week without remaking it.

        Reply
  1. Omg you are actually amazing. Everything I read up til now about DIY vitamin C was horrible and non scientifically backed.

    Amazing job Lab Muffin – this is exactly why your blog is one of my favourites!

    Reply
    • Thanks so much! I personally hate it when things don’t have proper reasoning behind them so I end up researching it and then hey, why not write a post on it? I’m glad other people also want that info!

      Reply
  2. You’re the actual best. Thanks so much for this. I’ve been considering buying a 23% LAA serum but wary in case it’s too strong. This is perfect, being able to adjust the strength. You continue to rock my world. Happy International Women’s Day you wonderful woman 🙂

    Reply
    • Thanks so much! 23% does seem a bit high. I would suggest diluting it with moisturiser or something as you use it, but I’ve never had any luck diluting things as evidenced by the crazy flaking skin I got using “diluted” 1% retinol and 10% BP…

      Happy IWD to you too!

      Reply
  3. That sounds super easy. I did know that vitamin C serum can be made at how, but all of them sounded a bit complicated to make. This is something I can actually see myself doing. Thanks for sharing!

    Reply
    • It’s very very easy! With full-time work I’ve gotten to the point where if it isn’t super easy, I probably won’t do it… I eat instant noodles a lot -_-

      Reply
  4. Hey! Not related to the post, but I’ve seen this article recently on another site claiming that most facial oils are harmful for your skin and that Squalane is the best facial oil. I think you use rosehip oil (correct me if I’m wrong… haha) and I have been using my rosehip from The Ordinary too. This lady has a lot of other questionable science on the other articles in her site (using on ‘natural’ products only, etc) so wanted to hear a scientific perspective/debunk of her claims. If you’re free of course!

    http://beautyeditor.ca/2017/02/22/squalane

    Reply
    • It’s BS! We have oxidisable fatty acids naturally in our sebum too. Keep using that rosehip oil! I might do a post debunking it at some point 🙂

      Reply
      • No, not really BS Michelle, this is due to an oxidation of the oleic /linoleic acids and their correct amounts in oils, some of them can be used only at night. For instance your rosehip oil is a night oil as it is rich in vitamin A.
        “Rosehip Oil contains Vitamin A as well as Vitamin E and is rich in linoleic and linolenic acids. It also has a higher percentage of naturally occurring carotenoids, resulting in a dark reddish orange color”.
        But the statement from that blog , that Squalane is THE BEST oil for skin is BS 🙂

        Reply
        • Carbon-carbon double bonds are inherently more unstable than single bonds, but there’s no evidence (that I know of) that the oxidation occurs on a timescale that’s relevant to skin application. There are loads of studies on oils containing linoleic/oleic acids where they’ve been used without light protection without any issues, and oils containing these are frequently stored without protection from light for months without issues.

          If there are any studies you can link to support your viewpoint, I’d love to read them!

          Reply
  5. Does it have to be labeled exactly L-Ascorbic acid? I visited my local supplement store and on the label of their pure vitamin C powers it said only Ascorbic acid not L-Ascorbic acid. Kare

    Reply
    • AFAIK it doesn’t matter because the industrial process for making ascorbic acid only produces the L version anyway! 🙂

      Reply
      • Doesn’t adding the water oxide the L-AA right away? This part confuses me. I thought that was the point of going with formulas that did not have water, but had E, and other “stuff” to make up the rest of the volume

        Reply
  6. This is amazing. I never knew you could do this. Definitely going to try this out!! Would distilled water just be in the bottled water section at the supermarket?

    Reply
  7. Thank you so very much for this! As a very broke grad student, this is a life saver! I’ve been looking at affordable vit c serums online for more than 2 months but didn’t buy any because I couldn’t part with my money. And I don’t trust those DIYs all over Youtube and Pinterest to make my own, because no qualified authority vouched for their effectiveness. But I trust you! 😀 Thanks again!

    Reply
    • IMO the arguments made in that article aren’t scientifically sound.

      1. This is really not much of an issue. Ascorbic acid won’t dissolve in oil, so apart from a plain water solution, it will either be in a water-based serum which would have the same issues as the ones claimed, or it’ll be in the water phase of an emulsion which could perhaps trap the ascorbic acid against the skin in water droplets… but you would do the same the moment you put on any other skincare products over the serum, or when your sweat and sebum mix with the ascorbic acid on your skin. That’s how anhydrous LAA products like those from Indeed Labs and The Ordinary work.

      2. Wrong pH – that’s why we adjust the pH with pH strips.

      3. Quick spoilage – we get around this by making it weekly, which is enough according to the paper I linked on the kinetics of LAA degradation.

      4. Fewer ingredients – there’s fewer benefits, yes, but we can just use other serums for those. Having a one ingredient product has the advantage of being more versatile with where you can include it in your routine.

      I’ve chatted with Stephen of Kind of Stephen, a cosmetic chemist, and he agrees that this serum should work (but would make a terrible store-bought product).

      Reply
      • Oh wow that was quick 😀 Thank you so much for your time replying!
        Whenever I see a discussion in the comments of a youtube video or something I can now share your blog entry 🙂

        Reply
      • that 1.) makes me think then how do all those other water solutions of vitamin C that are stable penetrate the skin then? Won’t they crystallise too?

        Reply
      • I just read the same article. The person Gio is awfully confident with her alleged knowledge and expertise with zero background in chemistry! I just shook my head and came to the comments here to see if anyone else mentioned that site…the name is laughable…I love your YouTube channel and articles!

        Reply
  8. This is so funny because I started making my own vitamin C after reading about its benefits on your blog, then I went on to buy on iHerb that exact brand of vitamin C powder that you’re showing on your pictures (as you had said that L-ascorbic acid was better). And it also turns out that I made some serum last week (time to make a new batch, by the way), but I emulsified it with vitamin E oil and some jojoba oil using lecithin. The serum’s still too liquid to be pumped, so I think that next time I might thicken it up with some xantham gum.
    xxx

    Reply
  9. Some terrific tips in this article, thank you! A couple of things I’ve found using vit c serum is firstly the smell – I always find it has a slightly unpleasant metallic smell – is it just me or has anyone else noticed this, and any suggestions for neutralising this? Also I have been using Vic C at night and if find it turns my pillow and anything I wearing yellow – again it could just be me! I find it impossible to wash these stains out too – really resilient.

    Reply
  10. Won’t the baking soda damage the skin? I read a post by Futurederm about baking soda and how she advises against using it on the face

    Reply
    • Nope! Baking soda is only bad for the skin because it has a high pH, but in this formula it’ll be a very low pH 3.5-ish. Under these conditions, the baking soda actually turns into sodium ions, carbon dioxide and water, all of which are harmless to skin except in very high amounts 🙂

      Reply
  11. Hello. Lovely article. Great to see Australian content on the Internet! I wanted to know when is the best time to use this and in conjunction with other things also? For example would you recommend at night before applying moisturiser, etc.

    Reply
    • I usually apply this either at night before moisturiser or in the morning before sunscreen. It works best applied on bare skin.

      Reply
      • Hi! Sorry to jump in on this comment. Thought it might be better than creating a new comment.
        I use a PC BHA at night. I am wondering whether I should apply Vit C before or after my BHA? Thanks!

        Reply
  12. So I have been using this now for a little over a week. I stored it in the fridge in a dark bottle. It didn’t change the color, it is still clear, not orange. But it did build some crystals. I thought it was because of the cold (it has been standing in room temperature for some hours now and the crystals didn’t dissapear). Since it hasn’t changed color yet I thought it would be still good to use but apperently I think it could have been bad already…because today I woke up with little tiny bumps all over my face and it’s also slightly red. At first I though something else must have caused it and tried to use it again this evening but it immediately burnt and so I ran to the bathroom to wash it off.

    Can the serum get bad without changing color and what does it mean when it starts building crystals? Is it normal that once it got bad it causes chemical skin burn? I thought it just wouldn’t be effectively anymore then.
    Do you think it was the serum? I didn’t change anything else in my skincare routine except I used some new cheap makeup brushes before washing them but other than that.

    I hope it will go away fast 🙁 I covered my face in Bepanthen cream.

    Reply
    • Oh no!

      I think the crystallisation might have changed what’s in the solution (e.g. the pH might have gone down if the basic components crystallised, or little crystals of vitamin C may have sprayed onto your skin to cause concentrated pockets of acid). If it does go bad, it shouldn’t turn into something that causes a skin reaction, so I suspect it’s the crystallisation.

      What concentration are you using? I’d recommend that next time you don’t put it in the fridge, and lower the concentration and introduce it into your routine slowly (once every 2 days for a few weeks, then build up slowly from there)!

      Reply
  13. I have been making it with just the VitC and dist water for quite a few months. After reading this, I realise I am using too much C although I do not have a bad reaction – just a 2-second sting. I have had amazing results but do not want to continue in case I damage my skin – especially now that it is spring and even though I use 50SPF sunscreen, I might be reversing what I have accomplished. I will now use your 20% calculation. Is the baking soda absolutely necessary? What does it do and what will happen if I do not use it?

    Reply
  14. I would be concerned about spraying it onto my eyelids and possibly getting it in my eyes. Seems that using it like toner on a cotton ball would be safer.

    Reply
  15. Hello,
    Could there be any issue with this recipe regarding microbiological safety? Please correct me if I am wrong, as I have no specific knowledge in this field, but can the lack of preservatives translate into bacteria contamination or something of this sort?

    Reply
    • Hi Silvia,

      I’ve discussed it at the end of the post, in the section “How long does this DIY vitamin C serum last?”

      Reply
  16. Hi Michelle!
    I’ve just made some C serum! It took about 20 minutes and 6 ph strips. I had to add about 7 rice grains worth of baking soda to brin the ph up to 3. I used hyaluronic acid, aloe juice, and vitamin E also. Could these additions be the reason that extra baking soda was needed to adjust the ph? Well, I’m gonna smear it on my face now! Thanks for the recipe!
    Cheryl

    Reply
  17. Such a beautiful article! I have been using DIY Vit. C Serum for a week now and i didnt know about the ph level. Wat a waste of one week of serum lol. So today I will test the ph level and adjust accordingly with baking soda.

    Another thing I used organic rose water replacing distilled water and the serum smell so good.

    Thank you

    Reply
  18. I mixed it, adjusted pH and then it crystallized on my face when it dried (i usulaly wait for c vit to absorb completely before applying anything else on). Second time I used rose hydrolate and same thing happened on my face? What did I do wrong?

    Reply
    • I think it might be good to apply something on top like a serum in that case. It sounds like the water is evaporating too quickly (dry or hot weather).

      Reply
  19. Thanks for a great article!
    Let me ask you something: the people from r/DIYBeauty seem to think you should only buy ingredients from cosmetic suppliers like Lotioncrafter, Personal Formulator and others like it. Regarding L-AA, do you think these suppliers are overrated? Thank you! 🙂

    Reply
    • I think they recommend that because a lot of natural products in particular (oils, extracts etc) vary in quality with heat exposure and just time… LAA is a lot more stable so it doesn’t make a difference 🙂

      Reply
  20. I’ve seen some improvements with my skin since using this recipe. I was wondering to what extent am I seeing improvement due to exfoliation, as compared to the antioxidants positive results?

    Reply
    • It’s hard to say! I’ve found that vitamin C doesn’t really exfoliate much though, as I still need AHAs, but that could be different for different people (oily skin, oxidative stress levels etc.).

      Reply
  21. This is actually an old swimmer’s trick! (Ascorbic acid is the active ingredient in most swimmer’s shampoos.) I’ve been using this for nearly 30 years to counteract chlorine. Although, “back in the day” we would drop a couple vit-C tablets in spray bottles with water & let them dissolve while we were in the pool. When we were done, we’d add some baking soda, shake, & shower!

    Several of my coworkers were Stanford grad students, most of which were in the health science fields. Put them in an environment surrounded by pool chemicals and, naturally, you end up with a non-stop geek fest! 🙂

    Reply
  22. The Ordinary is coming out with their 100% L-ascorbic acid powder sometime soon/someday, and I’ve also seen other brands selling powder as well. While The Ordinary hasn’t come out w/ explicit instructions, one Korean brand, Eco Your Skin, has instructions that say the powder can be mixed into serums or lotions. It doesn’t address the issue of pH levels that this post seems to revolve around. Does that mean that there is something fundamentally flawed with the way they are advising people to use their product? Should all these “diy” powders be mixed according to your recipe?

    Reply
    • You can mix them in, but the pH will probably be lower than you want. This isn’t necessarily harmful if your skin can handle it, but it can lead to unnecessary irritation.

      Reply
    • Hi Emily,

      Based on my personal experience, I bought The Ordinary’s L-Ascorbic Acid Powder and experienced a mild skin burn because of the lack of information on the packaging on how much product should be mixed with serums/toners/water. So yes, I completely agree with your point of view on the ill advised product instructions.
      It’s not like the product is bad, it’s just they didn’t give proper instructions on how to use the product.

      That experience led me to this blog post, which made me realize even further how many factors should be taken into consideration when using that product, pH levels, water content, amount of L Ascorbic Acid powder used.

      I’m buying pH strips now as we speak, will try this out with The Ordinary’s L Ascorbic Acid Powder. Fingers crossed!

      Reply
  23. Hi Michelle, so I have everything I need to make your vitamin C serum however I really wanted to include ferulic acid in the mix how would I go about doing that.

    Reply
  24. Hi Michelle,
    I’m going on holiday and would really like to take this Vitamin C serum with me for sun protection. I’m going in 2 days but I can’t find pH strips anywhere in store and it would take too long for them to come if I order online. Is there a way to get a round this? Can I just mix a little bit of the VItamin powder with my serum? I know quite a few companies have Vitamin C products that are meant to be used like that..

    Reply
      • I’ve actually been trying this out lately cos laziness, it seems to be working! There’s a danger in the pH being too low and causing irritation, but if you keep a sharp eye on that and back off if you notice any irritation, you should be OK 🙂

        Reply
          • Me too – particularly given the ordinary have just released their version of a powder, and they’re suggesting you just mix it with whatever. I would be super interested to know about what you could mix it with – I was wondering about rosehip, or moisturiser? I’d be so interested to know how much you should use.

  25. When adding the baking soda for pH adjusment, do you put the cap on and shake the flask for a proper mix or do you just stir it uncapped? Thanks!

    Reply
  26. I have read that the strateum corneum is pretty water proof. How exactly does Ascorbic Acid dissolved in water penetrate the skin? I have been researching to find out if this is the best most practical application or if there is something better. If you used squalane and an emulsifier, could you dissolve Ascorbic Acid into it without water?

    Reply
      • Hi Michelle,

        do you know how long it takes to absorb a vitamin C serum? Can I rinse it off after a while?

        Thanks for your great posts, as a long time reader of your site i really appreciate your work!

        Reply
        • I’m not sure on the absorption rate, and it will differ between product formulations, but leaving it on will be more effective! You can perhaps try it out and see what happens?

          Reply
  27. Does Ascorbic Acid powder expire? I bought some a while ago to make a more complicated serum, which I liked, but hated the work.

    This seems more reasonable to me. Would the powder still be effective?

    Reply
  28. Heya Michelle,

    I just came across a post claiming to solve the issue of Vitamin C stability in a very straightforward manner that is in-line (and nearly identical) to the DIY serum you already described above. You can find that comment near the very bottom of the page along with other’s on the topic here:

    http://chemistscorner.com/cosmeticsciencetalk/discussion/52/stabilize-vitamin-c

    Quoting:
    “I recall we have learned the method of stabilization the Vit C in the Medical University and I have found it. So, you could try it. Stabilization ingredients are Sodium Sulfite with the presence of Sodium Bicarbonate
    […]
    Ascorbic Acid -10.0%
    Sodium Sulfite -0.2%
    Sodium Bicarbonate – 4.7%
    Water – ad 100.0

    First the water should be boiled and cooled in a closed jar – it helps to rid the oxygen off the water.

    Then dissolve the sults and put the AA. Keep in a dry cool place in a dark glass container.

    Regularly they sterilize this solution. But I guess it would be preserved as well.

    Th pH of this stabilized solution should be 6-7 which is not bad for the skin as well.”
    —————-
    A few things:
    – there is no claim to the shelflife obtained using this method.

    – the pH is stabilized to between 6-7 which is way too high for our purposes.

    – if the shelflife turned out to be sufficiently longer, could a similar shelflife be obtained using lower pH, or would the decomposition of Sodium Sulfite (or other process) prevent this

    – from wikipedia “Sodium sulfite is decomposed by even weak acids, giving up sulfur dioxide gas.” Even if it could be used to stabilize at lower pH levels, I’m not overly fond of the idea of spraying rotten eggs all over my body, but apparently it’s also used to preserve apricots etc. so perhaps in low enough concentrations…

    Unfortunately and clearly, I’m no chemist, so I defer to your perpetual wisdom <3 … thoughts?

    Reply
    • I’m not sure – I’d like to see some data on the shelf life in terms of things other than the stability of the vitamin C! And like you said the pH is too high. But it sounds promising 🙂

      Reply
  29. Hi, sorry if this has been asked before. I did search but could not find it.

    I have been using 20% every night before going to bed. I did try it in the morning before putting on moisturiser and makeup but my makeup looked awful, so I prefer using it at night on clean dry skin and do not use any creams. The problem I have is that my pillowcase turns orange or a dirty colour. Also, my nails are orange because I must have them touching my face whilst sleeping. Do you have any experience with this and do you have a solution?

    Reply
      • How I wish! I am paler than copy paper and the serum makes me whiter. My pillowcase is disgusting to look at so I change it very often. The staining is only on 3 nails on my left hand (I am righthanded) with my index finger being the worst. I apply the serum with my right hand only and wash both hands immediately. I really thought I had an awful medical problem because it did not go away but I stopped using the serum and finally after about 3 months it is just barely visible at the ends. For me, it is 100% due to my nails touching my face when I sleep. When I am on my left side I hold the end of my pillow and that is when it makes contact! Sleeping on my right, my hand is never near my face. Oh the joys of trying to look better…

        Reply
  30. I’ve read that you can’t just add Vitamin E into this kind of mix (for the Vit C to interact with for the most photoprotective benefits) – the Vit E itself has to be emulsified first with another substance. Is this true? If I let your serum dry then just added Vit E on top would I get the same interactive benefits?

    Reply
    • I think if you layer them it’ll be fine. In a product it’s best if they’re mixed because the vitamin E would just float on top of the water-based layer like oil on water unless emulsified. I think perhaps a non-emulsified version would work if you shook it first?

      Reply
      • Thank you so much. I don’t have a science background, so I’m not even attempting to make any guesses here. I will put on the Vit C, let it dry so as not to fiddle with the ph, and then layer on the Vit E as you suggest. I’m not sure if the Vit E will have any effect at that point with the C, but if you say it may, then I’ll try it. I’d be curious to learn if does actually help.

        And just want to say, I have been making your serum for two weeks now, and sincerely appreciate the guidance you offer here. I bought the ph strips you recommended, but also have little micro measuring spoons so I can make it perfectly each time; it comes out so consistently around 3.2 (I make it every two days) I don’t feel the need to test the ph each time. So far so good. Thank you for your informative blog! If you ever want to get a column in a women’s beauty magazine you’d have my vote.

        Reply
  31. Any advice on how to include this into my daily routine without rendering it ineffective?
    One article I read suggested using it prior to moisturising in the morning after allowing it to dry 3-5 mins.
    I wonder whether this will reduce its effectiveness by essentially diluting or altering the pH post-application.

    Another article suggests the above prior to makeup. Moisturiser does reduce the sticky, I have found. Without the moisturiser though… I feel like I just had a bath in Orange Juice. Any solutions to the sticky you can think of (although this becomes pretty irrelevant if the moisturiser is ok).

    Side Note: Next time I go shopping I plan to buy one of those kids bags of sherbert with the tiny spades to use for accurate spoon measuring of the Baking Soda.

    Reply
  32. Thank you for the recipe! I’m gonna try it but I couldn’t find deionized water. I have a saline solution, though, which is deionized water with sodium chloride. Can I use it instead of just the water or will the salt ruin the serum? Or can I use just filtered, non-deionized or distilled water instead? Also, does the serum really get sticky and shiny? I couldn’t find vitamin c powder either, so I used an 1g ascorbic acid tablet with 10mg filtered water just as a quick test, and when the tablet melt I put it on my skin (without adding baking soda, but it didn’t burn my skin) and it got sticky and shiny. I don’t think the shine was crystallization, or was it? And the stickiness is annoying. Some people say vitamin c serums are sticky, some say they aren’t. A moisturizing cream over it got rid of the stickiness and shine, but I don’t know why. Do you know why? Sorry for all the questions. Thank you!

    Reply
  33. Hi Michelle,

    I love your site and it’s my go-to for evidence based skincare info – thanks so much for the work you put into it. I’m really curious about the ordinary’s new L-AA powder. It’s the same as any other ascorbic powder, right? I’m really confused by their directions for use, and I wondered if you might comment on it. They’re suggesting that you just mix it in with any other moisturiser or serum (I think excluding anything with EUK 134 or niacinamide) but I would have thought that wouldn’t really work, and you’d really irritate your face (or render it totally ineffective). Wouldn’t you just be able to mix any L-AA powder in with your skincare then, and you wouldn’t need to make it into a serum? They don’t even offer a specific amount to use, so I feel like people are going to melt their faces off.

    Reply
    • It’s the same as any other ascorbic acid powder, yes! I think the risk of melting your face off is pretty high. I’m working on a post on this! 🙂

      Reply
    • I’m working on an article on powders! But basically it’s the same as the bulk powder, just more crushed and more expensive. I would recommend adding it to a water-based product.

      Reply
  34. You and your posts are always fascinating and so well argumented. Also just read the article saying it was useless to make your own and had my doubts about some of their points, but you’ve now convinced me otherwise. Thanks!

    Reply
  35. Tetrahexyldecyl Ascorbate. Supposed to be more bioavailable for topical use? Is this an ingredient available for DIY skin treatment?

    Reply
    • It’s more bioavailable, but it doesn’t seem to work as well as ascorbic acid (or at least there’s very little data on its efficacy).

      Reply
  36. This is great information – thank you! I love the scientific explanation behind this. If you were to add glycerin, how much would you use, and is there a certain brand you would recommend? Would adding glycerin on the first try be too hasty?

    Reply
  37. Hello Michelle. I have ascorbic acid injection 500mg/ml (in a pharmacy) and would like to use it for the DIY. Can I just measure 1 ml of the ascorbic acid and mix with 9ml of water to get 10% vit C serum? Can it be that simple if I already have the vit C in solution (pH 5.5-7)? What is your suggestion on using this formulation of vit c to make my serum? TIA

    Reply
    • I think it’s probably better to make it from scratch – the pH is too high so you’d have to add acid to lower the pH anyway.

      Reply
  38. Hi Michelle! Very glad I’ve found you ? I’m about to DIY my vitamin C thanks to you. I have few questions though. I wanted to add glycerin and vitamine E but what would the quantities? I think I would take a 15 or 20 ML container.
    Thanks for your reply and keep being smart ?

    Reply
    • I’m not sure about the vitamin E – you’d probably need an emulsifier to keep it dispersed.

      For glycerin I wouldn’t go above 10% (it gets sticky).

      Maybe try a proper DIY recipe with preservatives? Holy Snails has a recipe here, you can probably just skip the ferulic acid if you don’t have it handy.

      Reply
      • I actually wanted to add it as a preservative, but you absolutely are right, I forgot that it won’t mix with water… I generally use seed grapefruit extract for water solutions. What do you think? I talked about it your post on glycerin (that I loved by the way)
        So the glycerin won’t inhibt the vitamine c power?
        I also read that you can just put some powder in another antioxydant ^^ not sure about this one
        Again thanks Michelle for your time
        I really enjoy your blog and YouTube channel, especially wen you robbed your face ?
        Enjoy the day !

        Reply
      • Oh sorry Michelle i didn’t see the link you’ve put. The receipe sounds interesting and promising but too complicated to me, I don’t know, I used to DIY plenty of things, but I’ve just gave up because I have no time anymore : children, husband and overwhelmed at the office. So now, I do read the ingredients and pay attention to what I buy. That’s why I do love your YouTube channel : it’s simple to understand, you are clear and your presentations work on the photographic memory 🙂 no need to go back to it !
        Anyway, did you try that receipe? From holly snail?

        Reply
  39. I would like to make the highest strength, but I’m not that good at multiplying.
    Could you please break that down for me?
    Also, what strength would the vitamin e be?i bought The Ordinary vitamin c powder, I’ll be using that!
    Thanks for the post. I’ve also shared with a group on FB!!

    Reply
  40. This post is about a year old now are you able to give any update on efficacy of this? (Assuming you kept using it) I looks super affordable (awesome) but I’d hate to waste 6 months with little result. I do understand Vitamin C can take some time to show its effects.

    Reply
  41. I felt so smug when I lined up all my supplies and started measuring and mixing ingredients. Then some frustration followed as PH was totally off before I even added bicarb. So now I’ve learned that Vitamin C (sodium ascorbate) is NOT the same as Vitamin C (ascorbic acid). Insert facepalm emoji:)))

    Reply
  42. Hi! Thanks for the great post. I’m planning on making a vit C serum with these ratios:
    66.66%, Aloe Gel, 20ml | 16.66%, Vitamin C, 5ml | 8.33%, Panthenol, 2.5ml | 8.33%, MSM (Methylsulfonylmethane), 2.5ml |
    Because the aloe gel is around 97% water I thought I might be able to use it instead of distilled water. The Panthenol and MSM have pH’s around 9-10 so I thought they may be able to bring the pH down to the appropriate 3-4 pH level.
    Do you think this formulation would work? I’m yet to test it out.
    🙂

    Reply
  43. Ive stated making my own serums thanks to you! But my serums never require baking soda as they are not too acidic so I dont need them but its good to have it handy just incase

    Reply
  44. Hi Michelle,
    I just stumbeled upon this article. Great article!
    I have a question about dissolving the vitamin c in water. How long will it take to completely dissolve?
    I have tried this before and I never succeeded in completely dissolving vitamin c power in water. Am I doing something wrong?
    Appreciate the help.
    Regards
    Marian

    Reply
      • Given that most things dissolve faster in warm or hot water, could the distilled water be warmed before adding the LAA? Or would the heat cause premature breakdown?

        TIA

        Reply
  45. I have quickly skimmed previous comments, but could not find an answer to my question. I’ve read that a good wait time for vitamin c serum is between 10 – 30 minutes. Some bloggers have suggested just to wait for the product to “glaze” the skin. What are your thoughts about any wait time for this particular recipe?

    Reply
    • I haven’t really experimented – I don’t think there’s any evidence either way. I personally apply a product on top almost straight away.

      Reply
  46. I have been using this every morning faithfully for three months, making a fresh batch every two days. I had a pigmented spot on my right cheek I hoped to clear up from a summer outdoors two years ago. I am a two on the Fitzpatrick scale for reference.

    Now I have some concerns – in spite of applying sunscreen every single day (and having very, very limited time outdoors as I have been ill), in the last three months more pigmented spots have appeared on both cheeks. Is it this serum? I am baffled as to why the spot issue is getting worse instead of better. Any advice? Thanks so much.

    Reply
  47. Hi Michelle, I ordered the nutribiotic ascorbic acid you recommended, still waiting for it to arrive. Meanwhile, I just read your other post where you say vitamin C can stain your face. OMG! I’m scared. I have rosacea prone skin so the last thing I want is change the color of my skin, which is kind of changed already by this condition. Do you use this serum on a daily base and if yes, have you noticed any “fake tan” on your skin?

    In order to avoid the stain you advised us “to immediately use oils and creams on top to protect the vitamin C from the air. Using it at night, away from high energy sunlight, will also help”. Ok, I was thinking of using it twice a day, but it’s better just use it once at night then, right? Will I totally avoid the stain using it just at night?

    I use azelaic acid to control my rosacea, do you think it can react with this serum? Besides, I’m not sure in which order I should be using it, please correct me: 1-Cleanser; 2-Michelle’s DIY Vitamin C serum; 3-azelaic acid? or 4-Moisturizer? and 5-Oil serum?.

    Please advice, Michelle, and thank you for all the hard work 😉

    Reply
  48. Hi Michelle,

    Thanks for your great recipe and all of the supporting research. Question for you: would apple cider vinegar work in place of the baking soda?

    Thank you! ?
    Katie

    Reply
  49. What a blog! I’m glad I found you. I’ve gotten pretty fed up with articles that uncritically believe marketing.

    I have a question regarding vitamin E; there’s a “water dispersible” d-Alpha Tocopheryl Acetate powder I’ve been seeing around. So far I haven’t found much about its effectiveness in water compared to oil, so I was wondering if you’ve heard anything about it. Do you think adding the powder to this serum would work well?

    Also, I’ve found some neat airless spray bottles on amazon, and I was wondering if they would make a difference in keeping the ascorbic acid stable. Non of them are opaque though, so they’d still need a foil outfit 😉
    Thanks!

    Reply
    • I think it would work reasonably well! It sounds like it has an emulsifier incorporated into it, but I think it’s best to contact the supplier and see if they can give you more information. If you want to keep it for a while, it’s probably a good idea to use an additional preservative as well.

      Reply
  50. Hi Michelle, thanks for the recipe! I like how easy it is. I have one question though. I searched DIY beauty thread on reddit and people always mention that mixing LAA with water makes a very unstable solution, and it loses half of its strength within 24h (why within 24h and not within a week like you mention in your post?). They recommend adding 1% citric acid as well. Now I’m confused >< should I add citric acid if I'm planning to remake the serum every 1-2 weeks? Looking forward to your reply!

    Reply
  51. Hi! I have tried this and used it on my face. Buy why does my skin feel gritty and “dry” afterwards? i guess maybe that’s because it lacks the slip and moisturizing agents most highly concentrated vitamin c serums have….

    Reply
    • putting sunscreen or other skincare products over it seems to fix the teture issue. But I am just wondering if this might be a negative indication to its inefficacy? Also, the form of vitamin C I used was Sodium Ascorbate…

      Reply
  52. Hi! My main concern with Vitamin C is just using it for its brightening and it s ability to reduce hyper-pigmentation. That is why i am debating on either doing this DIY for the long-haul or just purchase cheap to moderately-expensive (= $24) Vitamin C serum every three months like what Timelss and SKin Deva offers. I don’t care much for the inclusion of the Vitamin E and Ferulic Acid in the formulation if it’s not going to increase a Vitamin C’s ability to fade post-inflamatory HP and other HPs. Can you help me decide? And on that note (since you have tried other vitamin C serums before) was there a massive difference in your DIY Vitamin C and other brand’s Vitamin C in regards to brightening?

    Reply
  53. Hey Michelle! Do you have any tips to disolve the ingredients? Either the vit C powder or the Baking soda so that it dissolve nicely? I don’t like something scrub-y hahaha
    Anyway this is super informative! I would like to try make this one tho ?

    Reply
  54. Michelle doesn’t seem to be answering. I made her a cuestion a while ago about vitamin C staining the skin and what was her experience with vitamin C now that’s been a while she posted so she could talk a bit about any results, but no, she just skipped the questions, as many others and answered some with a line. Really, I don’t know what’s her criterium to answer cuestions. And if he raises a controversial subject, it seems unfair that she leaves us on our own.

    Reply
      • entitled? no, Michelle, this is taking you seriously when you don´t take others the same way. You are the rude person here, not able to address the points I raised, but just saying offensive words like you said. You’re just an (old) girl trying to be pretty (but sorry, you are not), and pretending to be intelligent, but you are just interested in your nails and you are selfish as hell. And I can tell you really don´t enjoy sharing with people, you’re just trying to get some attention, but you really hate interacting, that’s why you’re so alone and need to get attention from strangers on line, but you´ll never interact back as a human being, but the girl behind the make up worried about her big pores. Post it if you are a real woman!

        Reply
        • Gaba, it is very obvious here that you clearly lack any empathy.
          A human with empathy would be able to recognise that:
          a) Michelle writes her blog on the side of working full time therefore she is very busy. Life gets in the way of her being able to pander to your attention seeking.
          b) Michele has a lot of articles on her blog, and lots of people asking questions on each article. If one were to take even just a small moment, if it obvious that Michelle would get hundred of emails regularly. She replies to an awful lot of them! Your got accidentally missed. Mine did too and it was an easy question! But I got over it!

          Seen as you resorted to name calling and nasty bullying tactics, I will lower myself to your pathetic level.
          I am sick of seeing nasty narcisstic people like yourself, bring good people down and get away with it. So here I am standing up for Michelle.

          Gaba, your lack of empathy and severe over-reaction to Michelle not pandering to your entitled needs, makes it clear that you fall into ether one of these categories – Overt Narcissist, Sociopath, or Psychopath.

          Gaba, you need serious psychological help to deal with your narcisstic traits. Please seek help. If you live in Australia you can go to a GP and after being approved for a mental health care plan, you will receive money back from Medicare for each psychologist session that you go to.

          Gaba, you are a danger to yourself and to society. You need serious help.

          Reply
  55. I notice that you skip questions, especially the more complicated ones. We read your blog and try to use some of your ideas. But without further instructions, its hard to take you seriously. Staining your skin is serious stuff and you should share your experiences with your readers. Could it be that you’re not using your own DIY vitamin C serum but are instead using those expensive products that you review for us? We are entitled to know since your readers keep your blog alive.

    Reply
    • Well, now you’ve ensured that I will never answer your question.

      If you can’t take me seriously, that’s fine. Stop reading my blog. Don’t let the door hit you on the way out.

      Reply
      • I’m sure you don’t need my input Michelle, so forgive me for not managing to hold my toung. I think that if you truly gave such a poor impression to someone, they wouldn’t seek out your advice. It seems like a case of sour grapes because you didn’t magically solve this person’s worries.
        Gaba, I think it’s best if you do your own research to answer your questions, since only you know what factors are important for your particular situation. Try looking at the sources provided here or at other similar article and look up other studies relievent to you from the same publications. I understand that not getting answers can make one anxious, particularly when health or appearance is involved, but please don’t take it out on others.
        Michelle doesn’t owe us anything, and this blog is already quite generous in sharing her time and knowledge with us. It’s really not possible for her to answer every question presented here, because that would need extra time and effort for research that an individual simply doesn’t have. I don’t think that makes these questions pointless, however, because posting them gives the community a chance to chip in, and might allow her to notice reoccurring questions that she can chose to address (Correct me if I’m wrong).
        This blog can exists just fine without us; Michelle can do her own thing and interact with other members of the skincare science community without sharing publicly. Hopefully we can keep the privileged, and this sort of antagonism doesn’t happen again.

        Reply
  56. This is a really great post that really helped me. Recently I am using the LAA powder from The Ordinary. I have a scale that uses grams to calculate but I have never faced a problem with aqua based solutions since 1 gr of water = 1 ml of water. Now, I want to mix the powder with a propanediol based serum so there is a conversion problem. My only question is how could I measure the milliliters of an non water based product?

    Reply
  57. I mix the ordinary’s l ascorbic acid powder in with their Reservatrol and ferulic acid serum and apply most mornings. What do you think of this kind of application?

    Reply
  58. Hi Michelle, love your articles ! Thank you very much for the great tips and information!
    Because of the ‘jungle of information on internet’ I’ m a little bit confused about 3 things and I really hope you would help me, as I trust your knowledge and skills much and much more than all the other ‘gurus ‘
    1. On internet there are many diy recipes that combine vitamin E. Would you recommend it? Or is it better to use them separately, so first diy-serum c and after a few minutes pure vitamin e?
    2. Some sites/blogs say U need to wash this serum after 30 min or so? Is it true? And is it safe to use it daily?
    3. Can I mix LAA with other serum instead of water?
    Hope u can help!

    Reply
    • 1. IF you want to add vitamin E, I’d recommend using a formula with a preservative like Holy Snails’s formula so you can keep it for longer.

      2. Do you have a link to those sites or blogs? I’ve never heard that! In general vitamin C serums are left on, I’ve never seen any studies where it was rinsed off.

      3. You could but whether it would work as well depends on the serum – I wouldn’t be able to say.

      Reply
      • Thanks a lot for your reply, Michelle!!

        Regarding point 2, one of the sites/blogs is “it’s all in my hands” (https://itsallinmyhands.com/2013/04/09/diy-vitamin-c-serum/) . The blog advice to use this serum only once a week, and when use to wash it after 20 minutes. Here are some quotes from blog + comments:
        – “I would sugget to apply this Vitamin C serum everyday because it is quite aggressive. once a week should be enough”
        – reply on comment, 13 okt 2015: “yes, it is definitely too much to use it everyday. and yes i dont suggest using it for many hours. you should wash it off: what happens is that the serum oxidizes on your skin if you leave it there too long and this is not good. …”
        – reply on comment, 9 jun 2016: “you do the vitamin c serum, which you should wash off after 20 minutes or it oxidizes on your skin doing the opposite of what you want it to do…”
        Confusing, won’t you say?

        Reply
  59. Hi Michelle,
    I made this and found this to be quick enough. I was wondering that the container needs to be cleaned everytime a fresh batch is made? If not than will the new serum deteriorate quicker?

    Reply
  60. Hi Michelle,

    Thanks for sharing your knowledge! It’s great that you included tips to avoid common DIY pitfalls.

    I made a 20% vitamin C serum in a 20 ml bottle using your recipe, but it’s still clear after two weeks. The serum hasn’t turned even slightly yellow. The pH is below 3.5 and I’ve wrapped the bottle in foil. Do you think I made the serum incorrectly?

    Any help is appreciated. Thanks!

    Reply
  61. Hi Michelle, thank you for this very useful post. A question, probably a rather stupid one: could I also use bottled (drinking) water? Finding distilled water in Thailand is proving to be a bit of a pain, and bottled water (and the filtered water ‘on tap’ in machines) is cheap and readily available. Thank you!

    Reply
  62. Michelle,
    I have used vitamin c mixed with Epsom salts (magnesium sulfate) for my serum. I have read that magnesium ions stabilize ascorbic acid (vit c). Is this something you would recommend against? Also, would you still need to ad baking soda to it?

    Thanks,
    Ed

    Reply
    • They don’t stabilise vitamin C as far as I know, although there’s a stabilised version of vitamin C which is magnesium ascorbyl phosphate – is that what you mean?

      Reply
  63. I have acne-prone skin, and I use many ingredients in my skincare routine that Vit C isn’t supposed to play well with – nicainimide, AHAs, BHAs, retinol, mostly from The Ordinary. My toner is glycolic acid and used morning and night, I USE niacinamide in the morning and either retinol or BHA at night. I’d love the benefits of Vit C to fade acne scars, but I’m not sure how I could incorporate this without having it mix badly with my other stuff – or perhaps I’m using enough things that adding this would be too much. Do you have any Suggestions?

    Reply
  64. Hi Michelle, I’ve been stalking this post for years but buying my Vitamin C serums. I finally have Vitamin C powder aaaand PH testing strips. I also bought Kojic Acid powder! Can I add this, too?!? At a 1-4% concentration, of course!!

    Reply
  65. Loved the recipe and how you explained the why you put this way! Do you recommend adding vitamin E oil or Glycerin to the above formula? Thank you

    Reply
  66. Hi Michelle, I am defenitly going to make this serum! 🙂
    One questioin though. How much baking soda do you use? What volume/weight is 3 rice grains? Is it the actual weight of 3 actual rice grains?
    pH measure paper is ridiculously expensive in Norway, 95 AUD…, so buying that is not an option..

    Reply
    • Det er billig å kjøpe pH-strips på ebay! 😀 Jeg kjøpte mine der. Men en annen ting du også må være oppmerksom på, er at baking soda ikke er det samme som bakepulver. Jeg prøvde først med bakepulver, men selv om jeg brukte kjempemasse endret pH-en seg bare bittelitt 🙁 Jeg er nå ganske sikker på at det man skal bruke er natron! Testet litt med vann, og det endret pH masse! Legger du inn “natron” i google translate oversettes det til “baking soda” (vet at bakepulver på norsk oversettes til baking soda, men det er tydeligvis feil).

      Reply
      • Endte opp med ebay pH, men kjøpte den typen med bare en farge, så det er veldig vanskelig å se forskjellen på pH 3 og 4..Var heldigvis klar over at baking soda et natron! Av det jeg har testet trenger man ekstremt lite natron. Tar heller litt for lite enn å risikere at pH en kommer til 4, da den ikke er effektivt lenger da? Men om du har pH papir med 4 ferger, hvor mye natron bruker du til hvilket volum?

        Reply
  67. A bit worried about spraying on my entire face (eyes?). Could this be put in a rollerball bottle, or will the vitamin C react with the metal ball?

    Reply
    • Vitamin C should not come in contact with metal. When you are making your DIY Vit C, do not use anything metal.

      Reply
      • Not necessarily – depending on the metal, it’s generally only a potential issue if it’s in contact for prolonged periods because of the acidity.

        Reply
  68. Hi Michelle,

    I’ve been using this recipe daily now for years (probably since your 2017 posting?) and make a fresh batch every week at around 12.5 -15%. You asked how fast your readers can make it and I say it depends!

    If I sterilise the bottle with metho, I can add some extra minutes; if I let the bottle dry out before using it, I’ll let it dry overnight and make the batch the next morning;, if I use the cold tap water straight from the filter, it takes longer to dissolve the LAA but if there’s still a bit of hottish water in the kettle after my morning cup of tea to use, it dissolves almost instantly, etc etc. I long-ago abandoned the deionised water as it involved walking to the laundry cupboard to find it. I’m pretty good at eyeballing the bicarb now so I just need to pH test it once.

    Bottom line: A couple of minutes if I shortcut everything.

    For any nervous nellies out there worried about what might happen to your lovely youthful skin, it’s worked for me. I’m in my 50s and twice a day phial it into my palms to smear about the face and décolletage before a bit of Ordinary niacinamide then boring old sorbolene as moisturiser. No ill effects, except yes, slightly orange fingernails. Paint them if it’s a bother. Napi-san is how you deal with pillow cases and hand towels. Some age marks have definitely faded and my complexion has evened out rather well and I couldn’t be happier!

    Reply
    • This is really helpful feedback! Thank you!

      Make me want to try it myself, although highly doubt lazy me can keep doing it for years…

      Reply
    • Hi! Apart from your fingernails, did it stain your face as well? I really want to try this but I’m brown with pih and don’t want to end up with more stains on my face

      Reply
  69. ??????For alle skandinaviske som ønsker å lage sitt eget vitamin C-serum, så vil jeg tipse om at «baking soda» ser ut til å være «natron», ikke «bakepulver»! ☺️☀️

    Reply
  70. Thank you for this very informative article which also gave me an idea: do you think that one could make a niacinamide (vit B3) serum the same simple way given that B3 is also water soluble?

    Reply
  71. Hi, Michelle, thanks for an informative post!

    I just have a question regarding pH. Some articles advise against vitamin C powders due to the fact that without the right pH-level, the skin can’t absorb vitamin C in an effective way.

    Is that true? You don’t mention anything about the importance of the right pH-level regarding absorbation, so I’m curious to know what you think!

    Reply
  72. Hi Michelle,

    I came across this video looking up beauty videos on Youtube, while procrastinating when I should’ve been working. Unlike many beauty videos out there, yours is credible, factual, engaging and all your points are unbiased and backed up. It’s a really nice way to understand the most complicated science behind beauty – I thought I would never get to understand this science ever in my life lol! It’s also such a rewarding feeling to finally get a clear insight into this area without any prior knowledge about chemistry, so thank you! From the Youtube videos to the well written and laid out web pages, everything you have created has been so informative and at the same time, engaging and entertaining. You have a real talent, great wit and such an endearing personality, all which I admire and wish you all the best!

    Reply
  73. Hi Michelle, thanks for this article.

    I have a question regarding claims found online:
    Is it really better to add some lipophilic to any vit C product for better absorption?
    The argument was that the skin is both lipophilic and hydrophilic, so an exclusively hydrophilic substance would find it much harder to permeate anywhere.
    Then again it might be just the anhydrous lobby distorting facts. Any ideas/experience? Thank you!

    Reply
  74. Hey Michelle,is it fine adding baking soda in the serum? I mean I’ve read somewhere that baking soda has hazardous effects on skin

    Reply
    • It’s fine, the only hazardous thing is that it can lead to high pH, but here we have ascorbic acid to balance it out.

      Reply
  75. Hi Michelle,

    Quick question, I will be trying to weigh this vs volumetric, but I’m wondering if stainless steel or metal spoons will do anything to the Ascorbic Acid? I know with certain things, using metal can “deactivate” certain products.

    Thanks!

    Reply
  76. Hi Michelle! I made your serum, and added 3 drops of the Ordinary resveratrol+ferulic acid. And the mixture lasted 4 weeks before turning a very very pale shade of yellow, probably toward 3.5 weeks. Horah! Thank you for the recipe and hope this is interesting to you and readers 🙂

    Reply
  77. Thanks Michelle, very informative article, I’m new to this so there’s a lot to digest but its wonderful to be able to make your own product. I’ll have to go back and make notes as there’s a lot of info and tips in the comments. Its great to know this is working too, thanks so much.

    Reply
  78. I’m confused about how much distilled water to add. I have a 30 ml brown bottle and want to make a 10% solution. Thanks

    Reply
  79. I just discovered you!! And you’re already my favourite reviewer/skin-care aficionado! I’m going to be making this serum after once I run out of my current product.

    I’ve a question: I use this product at night and follow up with two moisturizers, one with Hyaluronic acid and the other with ceramides. After I apply the Moisturizer with Hyaluronic acid, I spritz water on my face. I was wondering if that water can cause the vitamin C to oxidize? I do wait about 2 minutes between layers.

    Reply
  80. Wow! I was slack. Added 1/4 tsp plus approx another 1/2 of that to a to 30ml bottle added boiled water. Few drops of glycerin and some citrus seed extract. My face feels amazing! pimples all disappeared with in minutes. I rubbed it all over my body it was so good. Fabulous. Thank you!

    Reply
  81. The products on my skin ball up if I use this DIY VitC serum with the Canmake Mermaid Gel UV (Clear) sunscreen. I let the VitC dry on my skin for 20 minutes, and I used different moisturizers* but still end up with the same balling effect. I don’t use any toners or essences btw.

    *Hada Labo Premium Milk, COSRX Oil-free Moisturizer, Illiyoon Concentrate Ato Cream

    Reply
  82. Thank-you so much for all this information!
    I asked Google a question about rash in my face when I use diy skincare, and I got to your info. I’ve made diy skincare fir years with good results, till I started making a diy vit C serum. Now I have a rash that won’t go away. After reading your info I realized my serum is far too acidic. I was mixing it into ACV, honey and camomile tea…..I ran out of the ph strips so I wasn’t testing the solution. Bad idea! So, for others reading this….use ph strips when you make a DIY….or you may suffer skin issues that are scary.
    Again thank you sooooo much for supporting this topic with your expertise! Hugs

    Reply
  83. This is awesome. I made mine with fresh aloe vera gel (from the plant) instead of water, which tested out perfectly on the PH levels, without adding baking soda. Any reason this combo is a bad idea?

    Reply
  84. Hi there,

    actually I own a SpoonWeighter, don’t know how it is called correctly. With it I could weight everything ecaxtly in 0,0gram, means it weights in minigrams too. So could you write for us cookingfreaks with a spoonmeasurer the exactly mg?

    Thank you!

    Reply
  85. Hi Michelle,

    First off, thank you for this recipe. I’ve been using it for almost a year now (on and off) and it’s really easy to follow and make fresh new baches!

    Now, question – could I use this recipe for making an EGCG serum as well? I figured I could take out the powder stuff from EGCG supplements and adjust the percentage using your equation. I’m not sure about the bacterial growth issue tho, any thoughts?

    Thanks!!

    Reply
    • The low pH is pretty important for preservation, I’d be hesitant to use EGCG this way. EGCG is pretty benign on skin though, so you might be able to do the “mix a pinch into moisturiser” method without much risk? Otherwise look into getting a broad spectrum preservative from a DIY supplier, then the world is your oyster when it comes to making any DIY serum 🙂

      Reply
  86. Hi Michelle, thank you so much for the recipe! I want to add ferulic acid to my serum but I read that it’s not soluble in water so do I need to include an organic solvent into the recipe so that ferulic acid can dissolve in my serum? If yes, which organic solvent should I use?
    Also how exactly is vitamin C “stabilised” by ferulic acid? Just curious about the mechanics behind this 🙂

    Reply
  87. I have thought so many times of entering the blogging world as I love reading them. I think I finally have the courage to give it a try. Thank you so much for all of the ideas!

    Reply
  88. Hello Michelle!
    Thank you sooooooo much for the recipe and the education that comes with it! I’ve been using a “brand” Vit C serum – I liked it, no irritation, but honestly, I just can’t bring myself to drop the $$$ for it every month. So I tried a DIY serum from another site – based on information here, I’m guessing now that it resulted in a 30% Vit C solution – the pH was approx. 3.5 and passed the elbow test but burned my face on a spot test. Yeoowwww!!
    This morning, using your formula, I made a 5% (approx) solution in a 10mL bottle I had from my prior serum. Enough to test for irritation – not enough to make me feel bad if it doesn’t work for me! I’ll start there and work my way up.
    Love your site – I’m just so sorry I didn’t find you years ago!!! Looking forward to reading everything you’ve posted!

    Reply
  89. Could I add niacinamide powder? If yes what percentage? Any other fun stuff to add? 😁 I love diy!

    Thank you!

    Reply
  90. Hi Michelle,

    Thanks so much for writing this up. I love no-nonsense advice and scientifically accurate advice on skincare, which you have generously provided.

    I have made a 20% L-ascorbic acid vitamin C solution in water using your instructions. When I look at the liquid inside the dropper, it is clear and the Vitamin C is totally dissolved, but after applying it on my face, there is always the white residue of the L-ascorbic acid powder left on top.

    I’m concerning maybe this means the L-ascorbic acid solution isn’t adequately penetrating/absorbing into my skin, if that makes sense? I can’t help but wonder why there would always be the residue left over on my face.

    Thanks so much, in advance 🙂

    Reply
    • That’s a bit weird, but if you put a moisturiser on top it should be fine – there are quite a few products with solid ascorbic acid that have been found to work.

      Reply
  91. Hello Michelle,
    I was wondering if I can get away with using a toner instead of distilled water? The Keep Cool Bamboo toner is very runny and soothing. I made a small batch, kept it in my skincare fridge – it started turning pale yellow after 3 weeks. I haven’t put it on my skin yet.

    Reply
  92. Hi Michelle,
    I followed your vitamin C recipe and it works exactly as you stated. It takes about 5-7 minutes to make. It will start to turn a light yellow after about two weeks. The powder form of L-ascorbic dissolves perfectly. I found Kombucha Chemistry ph test strips that only test from ph 0.0 to 6.0 which are ideal for this recipe. Thank you for this easy to make and use recipe. I appreciate the simplicity and exceptional cost effectiveness.

    Reply
  93. Hi Michelle,
    Wow, thank you so much for this article. I have stopped using all other Vit C serums since many have preservatives I don’t want to use— but never thought of making my own. I do have a question that is slightly different from your post. I used to use Philosophy’s Turbo Booster C powder- which is just Vit C powder that you just mix in when applying face creams, etc. It does have some other ingredients though.
    I have a large jar of L- Ascorbic Acid and I’m wondering if I can just mix it in with my face oils, moisturizers, etc without making up a bottle of anything in advance. Is that safe or would that burn my skin if I’m not neutralizing it first?
    Thank you so much. My mind is going wild with all of the possibilities!

    Reply
  94. Hi thx I am ordering items now!

    The ph strips link is broken tho 🙁

    Is there a way to add Vitamin E to this as Ive heard Vit E is good for the skin also? Or to add to skincare routine in another way / diff product? Or no Vit E at all is fine? Thanks

    Reply
    • Interesting! It does say that it worked at pH 7 but not at pH 6 though, which doesn’t make me very optimistic that it works at lower pH…

      Reply
  95. Hi Michelle, fantastic article! If using the same bottle of distilled water what do you think about pre-mixing the dry vitamin c and bicarb? Could potentially also add aloe vera powder. Then there would be no risk of microbial growth, but easier to make daily/weekly.

    Reply

Leave a Reply to Kristina Duka Cancel reply