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Vitamin C

vitamin c
October 6, 2010 Reviewed by admin 27 Comments

Ready for an overdose of vitamin C? Related information, I mean – it is actually incredibly difficult to sustain toxic reactions to this wonder nutrient. There is plenty of information available about vitamin C, but it can be difficult to discern what is pertinent and best for your anti-aging regimen.

But before I get to that, what exactly is vitamin C and is all the hype that surrounds it merited? Vitamin C, also known as ascorbic acid, is a water-soluble nutrient that, in addition to its antioxidant qualities and well-known role in boosting the immune system, synthesizes collagen.

In fact, vitamin C has been hailed as an anti-aging gem for some time now. According to research, vitamin C has been shown to help protect and repair skin cells. Not only does the nutrient wipe away free radicals, but it can also remove the DNA damage that the radicals form.

The visible benefits of this super vitamin? Wrinkle and hyperpigmentation reduction, protection against photoaging and collagen stimulation.

While you can get your daily dose of vitamin C from food sources like oranges, grapefruits, and strawberries there is significant proof that topical application of vitamin C serums may enrich your skin even further. The Journal of the American Academy of Dermatology published research that concluded, “appreciable photoprotection can be obtained from the combination of topical vitamins C and E.” And another study determined that spreading a vitamin C serum over your skin might correct aging-associated structural changes that occur over the years.

Sign me up! The fact that science supports the wonders of applying a vitamin C-infused cream make me all the more eager to slather some on right now. Unfortunately, things get a little complex once you’ve read and researched how vitamin C benefits your skin. Now comes the more difficult part – determining which of the countless topical serums is best and most effective in terms of improving and protecting skin. But before you decide what product is right for you, you should know the different types and derivatives of vitamin C that these products are made from.

L-Ascorbic Acid (AA) is vitamin C in its purest form. This unstable, water-soluble antioxidant seems to be the key to benefiting from the nutrient’s skin-rejuvenating powers. It is usually found in concentrations of 5 – 25%, though it is arguable what concentration is best for absorption. While some say a 10% concentration boosts collagen synthesis, others say the optimal amount is 20%, and still others claim that nothing over 18% can be absorbed.

Also important to ascorbic acid’s effectiveness is its pH level. The lower the pH level, the more stable, permeable and, therefore, effective it is. When its pH level is too high, it oxidizes, degrades and becomes inactive – or sometimes even a harbor for dangerous free radical formation.

What can be frustrating when shopping for the perfect vitamin C serum is the fact that the ideal, potent formula (high concentration, low pH) tends to irritate the skin. Still, there is a solution: using a topical based cream with no water will be less irritating since most of the inflammation is caused by hydrogen ions generated by acid disassociating in water.

Ascorbic acid is certainly a tricky substance in terms of stabilization and absorption. And sometimes, even if you do find a formula without water, it can still cause redness or other signs of irritation. Luckily, there are other options to explore for those seeking the advantages vitamin C has to offer. Synthesized vitamin C derivatives, including ascorbyl palmitate, magnesium ascorbyl phosphate, ascorbyl tetra-isopalmitoyl, tetrahexyldecyl ascorbate, and sodium ascorbyl phosphate are more stable and less irritating than ascorbic acid. The question is, are they more effective?

Ascorbyl palmitate (AP) is a vitamin C ester, which means that it has been esterified to a fatty acid. It is fat soluble as opposed to the water-soluble ascorbic acid, which may hinder its ability to penetrate skin. Also, ascorbyl palmitate produces different short and long-term effects compared with ascorbic acid.

Magnesium ascorbyl phosphate (MAP) is similar to ascorbic acid in that it is water-soluble. However, it also has what AA lacks: a gentle effect on skin, efficacy in lower concentrations, and stability at a neutral pH. In one study, researchers discovered that it was statistically more effective than ascorbyl tetra-isopalmitoyl (see below) in free radical reduction, although less so than AA. However, it does seem to better quench the deeper layers of skin than ascorbic acid.

Ascorbyl tetra-isopalmitoyl (ATIP) is a vitamin C derivative. It is stable, due to being fat soluble and less irritating than ascorbyl acid. There is a 2006 study that concluded that it can suppress UV-induced skin pigmentation at a 3% dose. Tetrahexyldecyl ascorbate plays nice with vitamins A and E and UV filters. One study published in Dermatologic Surgery in 2002 showed that a topical formulation combining 10% vitamin C and 7% tetrahexyldecyl ascorbate improved hydration and collagen synthesis in the skin and resulted in "clinically visible and statistically significant improvement in wrinkling" after 12 weeks. A 2009 study claims that it can actually prevent UV damage occurring.

and effective at a lower concentration. However, ATIP seems to be a poor performer when it comes to penetrating skin.

Sodium ascorbyl phosphate (SAP) is known to promote collagen formation, and its ability to be stabilized for at least 24 months if it is stored in the original sealed containers at 25 degrees Celsius.  It is also being lauded as an effective acne fighter. Still, it is a fairly new derivative, so there is not a great deal of research comparing it to ascorbic acid.

So, how do L-Ascorbic Acid and its derivatives stack up against each other? Overall, it seems that AA is the winner and champion when it comes to vitamin C and skin care. One study revealed that topical application of ascorbic acid outperformed both MAP and ATIP in antioxidant potential. Another study showed that AA permeated the skin more effectively than MAP in gel and cream formulations. Finally, a study comparing the effectiveness of AA in anhydrous solutions revealed that MAP and SAP both have negligible free radical foraging ability compared to ascorbic acid.

While some derivatives (like Magnesium ascorbyl phosphate and Sodium ascorbyl phosphate) seem to have noteworthy benefits, it is important to make sure that L-Ascorbic Acid is near the top of the ingredients list when searching for vitamin C creams. Though, perhaps an ideal serum would include first and foremost ascorbic acid, followed by smaller amounts of a derivative.

  • December 10, 2018

    by Nikola

    If Ascorbic Acid is most effective, and it need low PH to be effective - isn't simple lemon juice fulfilling these criteria? Am I missing something?

    I mean, we could just rub our skin with leftovers of any fruit we have just eaten? There would be lots of beneficial vitamins (Vitamin A, vitamin C, Niacin)

  • November 1, 2018

    by Qi Yong

    Thank you for the great article, I was just researching products with Vitamin C. There are many claims made by different brands, with some brands coming up with unorthodox ways of preserving shelf-life (microcapsules in serum but with the less effective type of vit c). This list really made things easier for me and I like the fact that you weighed both shelf-life and efficacy for the different derivatives of Vit C. Would be even better if you guys included ascorbyl glucoside though.

    Great Article!!!!

  • February 6, 2018

    by Sid

    I have been researching extensively the best form of Vit C for skincare and turns out the pure L Ascorbic powder is the best in terms of the amount of benefits it provides (although most acidic and unstable) but It can be made on a weekly basis batches to give best results for a fraction of price of commercial products. I am however thinking if making a serum of vit C with water or oil would be a better option for stabilising it longer. I guess I might have to experiment it myself sadly!

  • January 24, 2018

    by Ronnie

    Well that just sucks! Ascorbic acid irritates the **** out of my skin. I've tried so many different serums and products with it throughout the years but i've never been able tolerate topical C beyond a week (usually after 3 days my skin is perpetually red and often broken out). I can't find any affordable serums at a low concentration or if I do, they usually have tons of other crap in them (especially oil, which inevitably leads to breakouts for me). The low PH definitely causes me irritation.

  • January 9, 2018

    by Camilla

    Is Ascorbic Acid synonymous with L-Ascorbic Acid?

  • August 30, 2016

    by Pam

    This sounds like the NCN Pro Skincare Vitamin C+ Serum with 20% L-Ascorbic Acid, MAP, Vitamin E, Glutathione, Ferulic Acid, Oat Beta Glucan, etc.

  • July 27, 2016

    by Marta

    Hi Ty, we have an extensive ingredients database, so if you ever want to check out a product's claims, you can look them up. MAP is indeed a stable form of vitamin C and good to have alongside AA. There is more information here:

    Glutathione regulates antioxidants such as vitamin C, vitamin E and lipoic acid. There is more information here:

    So, what is the product in question? Sounds interesting.

  • July 26, 2016

    by Ty

    What are your guys thought's on this products claim?

    "Studies and tests have proven that the best Vitamin C Serums are made with L-Ascorbic Acid due to its ability to penetrate skin. The only problem with L-Ascorbic Acid is that it isn’t stable; it oxidizes quickly, deeming it ineffective. However, we have solved that problem with the addition of Glutathione & MAP (Magnesium Ascorbyl Phosphate). Glutathione stabilizes l-ascorbic acid (Vitamin C) and Vitamin E. Glutathione rapidly depletes with age, stress, and the environment. It’s our best defense against accelerated aging. The addition of Glutathione in this formula makes it a real anti-aging powerhouse!

    Glutathione, known as the body’s master antioxidant, is part of the body’s natural antioxidant systems. Many of the most commonly used antioxidants work by regenerating glutathione. It is a primary antioxidant that neutralizes current, and prevents future oxidation."

  • January 14, 2016

    by George

    Nothing compares to L-ascorbic acid! The only problem is that the companies that manufacture these products do not reveal their potency. Demand products that contain 20% to 35% pure L-ascorbic acid. Avoid derivatives. Also demand stabilized L-ascorbic acid in order to avoid degrading products. which discolor. This type of product is ideal and it will do the exceptional job on your skin. It may tingle a little bit, but you will be rewarded when you look at yourself on the mirror.

  • October 11, 2015

    by sayara

    I making my own serum using vitamin c powder mixed with water, vegetable glycerin and oils (jojoba, avocado, coconut ... etc) is this safe?

  • March 12, 2015

    by Melody Dál

    If L-Ascorbic acid is water-soluble and unstable why would it be the best option for topical use?
    I'm currently using a product with AA but I've been told that magnesium ascorbyl palmitate is better to use since it is a fat-soluble derivative which allows it to be absorbed by the skin, as opposed to AA.
    Does combining AA with vitamin E contribute to the level of absorption of the vitamin C in any way?

  • February 12, 2015

    by Gita

    "L-ascorbic acid must be formulated at pH levels less than 3.5 to enter the skin. Maximal concentration for optimal percutaneous absorption was 20%. Tissue levels were saturated after three daily applications; the half-life of tissue disappearance was about 4 days. Derivatives of ascorbic acid including magnesium ascorbyl phosphate, ascorbyl-6-palmitate, and dehydroascorbic acid did not increase skin levels of L-ascorbic acid."

  • December 5, 2014

    by Vic1981

    Tetrahexyl ascorbate due to its molecular structure and solubility, penetrates cutaneous layers more readily as opposed to AA.
    In regards to your comment about formulation containing all forms, MAP and SAP have different ph requirements, ranging 5,5-6, whereas AA has to be incorporated into formulas at low ph approx. 3.4-3.7. MAP, SAP or tetra wuld not be stable in such a low ph.

  • September 18, 2014

    by Blare F

    Compared to "unstable vitamin c -L-Ascorbic Acid", I'd like to choose "stabilized vitamin c- sodium ascorbyl phosphate"! I bought both from Amazon, the first AA serum became bad only after opening for less than 1 month and smells awful! the second one is stabilized vitamin c with sodium ascorbyl phosphate, has 2 years shelf life! I've used it for about 6 months and my skin looks perfect!

  • May 26, 2011

    by Marta

    Hi Dennis, thanks for sharing.

    I did a Five Best with vitamin C at the beginning of the year"

  • May 26, 2011

    by Dennis

    I'm obsessed with tetrahexyldecyl ascorbate lately! my scrub, face wash, and night time serum are all loaded with it. If you don't mind I would like to share this with the users.

    My scrub is Dermalogica's multivitamin thermafoliant. This is one of my favorite scrubs ever. The 'Dew' factor after use is the best I've come across. My face wash, and this might be of particular interest to men, as it is in a mens line, is Billy Jealousy White Knight Gentle Daily Facial Cleanser. It's a lotion cleanser, but like no lotion cleanser I've ever used - it's sort of a foaming lotion. Finally at night I'm using Skin Organics Super C-15 w/ Idebenone. It's 15% Vit C! and smells delightful.

    Marta, maybe you can do a post on Vit C products?


  • October 9, 2010

    by Jennifer

    There are so many things to consider with vitamin C, you have made very good points. You get what you pay for with everything.

  • October 7, 2010

    by SarahK

    Very good point about the Whole Foods List, I completely agree. We should definitely have access to not just what is on the list, but also reasoning as to why they are listed.

    And thank you for the clarification Barbara, I appreciate the insight.

  • October 7, 2010

    by Barbara

    Hi Sarah,

    As a cosmetic chemist I can assure you tetrahexyldecyl ascorbate = ascorbyl tetraisopalmitate. You may check it with the Japanese manufacturer.

  • October 7, 2010

    by Julie Kay

    Thanks for your insight into Whole Foods, Darrell! I've never cared for the store; I do my "organic" shopping at PCC or Trader Joe's. Plus your ps on Vit C is extremely useful knowledge. I'm soaking it up!!! ~jk

  • October 7, 2010

    by Darrell Owens

    I'm glad to have learned about the Whole Foods Market list mentioned above.

    I heard once before that Whole Foods maintains internal lists for their Corporate buyers that encourages the avoidance of certain ingredients when seeking products for the store shelves -- guidelines that help them purchase natural and organic products. I was curious and so I took a look.

    Now having looked at the list, it seems irresponsible that Whole Foods publishes without context.

    As published, many reading the Whole Foods Unacceptable Ingredients list might glean that the ingredients listed are harmful and should be avoided by consumers -- when really, it's just a list of ingredients Corporate buyers of natural and organic products might avoid.

    There are indeed many ingredients on the list I would personally avoid as a consumer and, if I were a buyer seeking to stock my shelves with natural and organic products, the list might be helpful.

    There are many ingredients on the list that are extremely helpful, beneficial and that protect consumers. So overall, I feel the Whole Foods list does more harm than it does good. I'd be curious to find just how closely their buyers are following their own list.


    P.S. Just a side & opinion on tetrahexyldecyl ascorbate/ascorbyl tetraisopalmitate. It's the only vitamin C I know of that's gentle and can be tolerated by just about anyone; no matter their level of skin sensitivity. It's also more stable and doesn't oxidize like other vitamin C's, which may make it more appealing.

  • October 7, 2010

    by SarahK

    DIY formulas are definitely a great idea! You can click here for some more ideas and tips:

    Barbara, thank you for your comment. I researched what you said about tetrahexyldecyl ascorbate and ascorbyl tetraisopalmitate being equivalent, and did come across some information that may support that. However, when writing this article, I used this as a reference:

    On page six, it lists derivatives as such:

    "ascorbyl-6-palmitate, magnesium ascorbyl phosphate,
    tetrahexyldecyl ascorbate, ascorbyl glucosamine,
    and ascorbyl tetraisopalmitate"

    To me, it sounded as though tetrahexyldecyl ascorbate and ascorbyl tetraisopalmitate are two different things.

    In terms of the safety of Tetrahexyldecyl ascorbate, I just found it a bit odd that it is placed on the Whole Foods Market Unacceptable Ingredients to Premium Body Care list. I don't claim that Tetrahexyldecyl ascorbate is unsafe; I am merely pointing out facts that I discovered during my research.

  • October 6, 2010

    by Junko

    Great article SarahK! Makes me feel even more confident about the DIY vitamin C, Ferulic & E I've been mixing up & using since I used up my Eshee's Vitamin C! Has helped even out my skin tone. Here's a basic recipe that's fun to modify & NOT for sensitive skin. 1/2 t L-Ascorbic Acid dissolved in 1 1/2 t water; Pinch Ferulic Acid dissolved in 1/4 t witch hazel; 1/8 t Vitamin E oil mixed with 1 t cream (maybe YBF concentrate). Mix together put in dark dropper glass. Keep in fridge. A bit tacky or sticky so use at night.

  • October 6, 2010

    by Barbara

    There is not chemical named: Ascorbyl tetra-isopalmitoyl.
    There is chemical named ascorbyl tetraisopalmitate, which is exactly the same ingredient as tetrahexyldecyl ascorbate. These two names are synonyms.

    tetrahexyldecyl ascorbate = ascorbyl tetraisopalmitate

    Tetrahexyldecyl ascorbate is made by the only one Japanese company who done a lot of studies on it. Barnet company is only a distributor of that ingredient to US, they haven’t done any research. Tetrahexyldecyl ascorbate is a safe ingredient, used in OTC products in Japan so called Quasi-drugs.
    It is easy to made a list of unacceptable ingredients, but without a studies and explanation why any ingredient is unacceptable such a list is worthless and only brings confusions.

  • October 6, 2010

    by Diane

    I realize that the purpose of this site is to review products but I feel obligated to pass on cheap and effective solutions. The website (I have no connections to this website other than as a visitor) has DIY formulas for many products, including vitamin C serums and lotions. Considering the downsides (cost, expired product, questionable concentration) of vitamin C products, I always make my own.

  • October 6, 2010

    by Lisa

    Wonderful information! Vitaman C can be so darned confusing. I am bookmarking this to study it so I don't get so tongue tied about it when discussing it. Thanks!

  • October 6, 2010

    by Angela J

    Hi SarahK, Thanks so much for clarifying the differences between all the forms of Vitamin C that are out there. It can get so very confusing, and an article like yours really helps in knowing what to look for.

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