Beauty Tips For Body Care
This was an Adderall fueled post. I’m about to nerd out big-time here. Scroll down for TL;DR!First, why do I care about vitamin c? I recently decided to add a vitamin C serum to my skincare routine because of all the great effects I’ve read about. Really, it seems as skincare ingredients go, vitamin C is amazeballs, and I’m not talking anectodtal “OMG it made my skin feel so much better” shit, I’m talking legit scientific research showing several skin benefits. It’s a fucking fabulous antioxidant, it is photoprotective against UVA and UVB stress, it is an essential ingredient for collagen synthesis AND upregulates (causes) collagen synthesis, and it is effective at preventing and lightening dark spots through inhibiting the enzyme Tyrosinase, which is the rate limiting enzyme for melanine production1,2 . AND, do you like Vitamin E? Because Vitamin C regenerates oxidized vitamin E molecules so your body can use them all over again3 !We’ve known the much of the details of the dermatic glories of Vitamin C for over fifteen years. Clearly, we all want lots of vitamin C. Some of this can be provided in our diets, but gastric absorption of vitamin C is downregulated by the levels of vitamin C already in your body, which means most of that supplement you have been taking just gets peed out (but I’m sure the fish appreciate it). So, in order to elevate the levels of vitamin C in our skin, it needs to be applied topically. Problem is, Vitamin C (ascorbic acid) is a tricky motherfucker. It’s SO effective because it’s so reactive as an antioxidant, which means it’s got major stability issues. It oxidizes REAL quick in solution, and this oxidation rate increases along with temperature, air, and light exposure. My guess is this is why vitamin C only recently surged in popularity as an ingredient in skincare products; manufacturers are certainly getting better at formulating (for instance, adding Ferulic acid to stabilize vitamins C and E4 ), manufacturing and packaging products in a way that maintains their effective shelf life. The problem is, not every manufacturer is actually going to spend the time and money to ensure quality, and many companies may just ride the Vitamin C bandwagon without considering these things or caring if it is actually effective in their product.Why am I concerned about pH? Problem number two with vitamin C products is their pH. We’ve heard time and time again that it is important for the pH of skincare products to remain low to ensure efficacy. A quick Google Scholar search brought up an article on the effects of pH on Vitamin C absorption in particular5 . The researchers showed that in a solution of a pH 4 or above there was no detectable increase in skin vitamin C levels (it wasn’t absorbed), while vitamin C levels are elevated at a pH of 3.5 and increase as pH lowers. This same study also showed that the best concentration for maximum vitamin C levels is 20% (for some reason there is a decrease in vitamin C at higher percentages) and that even though it is the least stable, L-ascorbic acid is the best ascorbic acid derivative to use.Choosing a Vitamin C Product Given all of this fantastic information, I am convinced that pH is a critical factor for an effective vitamin C product. Unfortunately, as a poor graduate student, my choices in skin care products are financially limited. Given that I have science, I decided to also try making my own. I purchased some vitamin C L-ascorbic acid crystals from the Vitamin shoppe and ground them into a fine powder using a mortar and pestle. I then used a digital scale to measure out the powder and, using deionized water and glycerol, made a 20% weight by volume solution of L-ascorbic acid serum. I actually really like how it turned out. I used this first and saw visible improvement in the redness of my skin after a week or two.Still, I wanted to try something “real.” Much as I’d love to, I can’t usually spring for the expensive, already researched and well reviewed products, and so I searched Amazon for a cheap alternative. I settled on ArtNaturals Enhanced Vitamin C Serum because it was under $15, claimed to contain 20% Vitamin C, and had many positive reviews (4 out of 5 stars from over 9000 reviews).The first problem I noticed with this serum was in the ingredients list – it does not contain the L-ascorbic acid form of vitamin C, but instead what is reportedly an aqueously more stable, while less studied form called Sodium Ascorbyl Phosphate. I didn’t sweat this too much, because it wasn’t tested in the earlier study5 I mentioned, and a more recent paper reported good absorption levels6 . I wasn’t impressed. It wasn’t bad, but it didn’t seem any better than the serum I made. It was actually a bit sticky, comparatively, and my skin didn’t tingle like it does with my DIY serum. I decided to test the pH of both serums, and WOAH.Testing the pH – RESULTS! First, let me show you how the pH test strips I used work using vinegar and water as examples/controls. The strips are wetted in the solution for 1-2 minutes then compared to the swatch which shows pHs from 0-14 at 0.5 intervals. There are 8 dyes that are affected, and the closest swatch match is used. This example shows, from left to right, vinegar, vegetable glycerin (glycerol), bottled purified water (Dasani), and city tap water. As expected, vinegar was the most acidic, but it fell in at around 1.5-2. That’s actually more acidic than you’d expect from white vinegar (~2.5 pH). Glycerol and bottled water checked in around 6.0 again, a bit lower than expected, and my tap water was ~7.0. I didn’t have any buffer to check these strips with (I’ll test them tomorrow in my lab), but it looks like might be showing acidity a little low. If so, it looks like it might need about a +1 correction term, but because pH is a logarithmic scale I can’t be sure. Anyway, we can at least move forward and see our pHs relative to vinegar and water!Next, I tested my homemade 20% L-ascorbic acid serum. It is about 3-4 weeks old, and is stored in a dark glass dropper bottle (an old Korres serum bottle). I was shocked to see it falling in at a pH of 1.5, right where the vinegar was. If it IS 1.5, that is stupidly acidic, not to mention virtually impossible to achieve. L-Ascorbic Acid is a diprotic acid with pKas of 4.17 for the first proton dissociation, and 11.57 for the second. This means, given the maximum saturation concentration in water of 33%, I’d only get a pH of 1.87, which would look closer to 2. Visually, its similar to the vinegar, so my guess is it’s a pH of 2.5. I’m actually pretty happy with that. I’d almost call it too acidic, but my skin is responding well to it, so I’m content.Now for the shit I bought off of amazon! Are you prepared to be impressed! Well, sorry to disappoint you, but this shit was basic.. Okay, not very basic, but around or above neutral. Visually, I’d call it 7.5-8. Even if my strips are showing things as a bit lower in pH, it’s more basic than the water I used as a control, and not anywhere CLOSE to the necessary effective pH of <3.5. This stuff is absolute shit.I will concede that this isn’t the same type of vitamin C used to determine pH/absorption profiles. However, the skin has a pH of around 5 and generally a lower pH is considered necessary to maintain effectiveness and to be absorbed into the skin, as shown in studies for other nutrients7 . I'm probably going to keep making my own serum. I may actually buffer it up to a pH of 3 with some sodium hydroxide once I measure it with a calibrated pH probe in my lab (tomorrow).My curiosity also lead me to test a few of other products that I use regularly.*Alpha Hydrox 12% AHA Soufflé (glycolic acid): pH 4.0-4.5*CeraVe Renewing Salasylic Acid Cleanser: pH 4.5*Retin-A Micro 0.08% Pump: pH 4.5*Dermapeutics Kyaluronic Lift Serum: pH4.0-4.5I hope you found this somewhat interesting. I certainly did, which is why I just spent 2 hours testing and writing about it! It’s probably not a bad idea for everyone to test their products for pH – test strips are relatively cheap, and it’s easy to do at home and important information to have!SOURCES CITED:Pinnell, S. R. (2003). Cutaneous photodamage, oxidative stress, and topical antioxidant protection. Journal of the American Academy of Dermatology,48(1), 1-22.Farris, P. K. (2005). Topical vitamin C: a useful agent for treating photoaging and other dermatologic conditions. Dermatologic surgery, 31(s1), 814-818.Lin, J. Y., Selim, M. A., Shea, C. R., Grichnik, J. M., Omar, M. M., Monteiro-Riviere, N. A., & Pinnell, S. R. (2003). UV photoprotection by combination topical antioxidants vitamin C and vitamin E. Journal of the American Academy of Dermatology, 48(6), 866-874.Lin, Fu-Hsiung, et al. "Ferulic acid stabilizes a solution of vitamins C and E and doubles its photoprotection of skin." Journal of Investigative Dermatology125.4 (2005): 826-832.Pinnell, S. R., Yang, H., Omar, M., Riviere, N. M., Debuys, H. V., Walker, L. C., ... & Levine, M. (2001). Topical L‐ascorbic acid: percutaneous absorption studies. Dermatologic surgery, 27(2), 137-142.Fočo, A., Gašperlin, M., & Kristl, J. (2005). Investigation of liposomes as carriers of sodium ascorbyl phosphate for cutaneous photoprotection.International journal of pharmaceutics, 291(1), 21-29.Becker, F. F., Langford, F. P. J., Rubin, M. G., & Speelman, P. (1996). A histological comparison of 50% and 70% glycolic acid peels using solutions with various pHs. Dermatologic surgery, 22(5), 463-465.TL;DR*Vitamin C must be acidic (pH < 4) to be affective.*ArtNaturals vitamin C serum from Amazon has a pH higher than water, around 7.5.*My homemade 20% vitamin C serum is pleanty acidic, and I can make it fresh so don’t have to worry about it oxidizing before use!*pH Test your products! It’s cheap, easy, and important!Disclaimer: I am a biologist, and therefore I am comfortable calculating, measuring, and making solutions. I also understand the potential biochemical effects of various ingredients. Don’t make stuff at home unless you know what you are doing, and always test a small area on your skin first!
Girls Blog 2015
Submitted by wholligan
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