Antioxidants in Skincare Formulations
Antioxidants are all the rage these days in both skin care products, supplements, as well as in foods, but what are they, and what exactly do they do? Do they work, and how effective are they? Sometimes with all the hype, we forget to question the basics.
What is an antioxidant anyway?
We are told that antioxidants are the universally accepted good guys - vegetables, fruits, eggs, legumes, nuts - they definitely have good PR - and are in many healthy foods with plenty of vitamin C and E. What are they though, and how do they work? At a basic level, antioxidants counter and resist the effects of oxidation. Watching an apple turn brown when exposed to air demonstrates the chemical reaction of oxidation1. At a micro level, when a molecule has an unpaired electron, they become unstable, taking one from another molecule, which then has an unpaired electron, causing a chain reaction2. This isn’t a catastrophe, however. Oxidative stress is simply an inevitable and essential part of our biological process3. It just happens that it’s why and how we age (get wrinkles, mottled skin, some skin cancers) and are not immortal. Oxidative stress also accelerates when the skin is exposed to the sun, or when the air is polluted or when we smoke cigarettes or drink alcohol4. So oxidation is associated with slow damage that causes us to age, and antioxidants fight this effect in theory.
Antioxidants are molecules that are stable without an electron and have a free electron that they can help donate when an unstable free radical needs one. Essentially, they act as shields that will sacrifice their electron so that the more essential cells aren’t disrupted. Your body naturally produces and has some antioxidants. As oxidation is required in many biological processes (all living things age), there is a mechanism designed to control the damage that’s inherent in this process as well, and they’re called antioxidants. Antioxidants in foods, supplements, and indeed, cosmetics, is to provide the body with more of these protective molecules that help control the damage that oxidative stress causes.
Antioxidants in Foods: Murky Data
Any craze as big as antioxidants usually have skeptics forming a line to attack them from various angles. At least in terms of dietary intake, however, foods that tend to contain high levels of antioxidants are also generally healthy for other reasons as well. It’s tough to start attacking onions, tomatoes, green tea, and grapes en masse without looking like a charlatan (I mean, what’s left to recommend? French Fries?) There are a lot of charlatans that sell hype in the field of diet and nutrition, but even without ill motives, there’s so much noise and so little reliable data that it’s very difficult to pinpoint exact truths in this field5. In short, there are many unanswered (or only partially answered) questions:
- How strong is the evidence for antioxidants, and is there a way to isolate its effects and measure this empirically?
- Are these superfoods healthy because they have lots of antioxidants or because they're just healthy foods that also contain antioxidants?
- Can you have too much of a good thing, especially when they get concentrated into supplement form?6
- Oxidants and antioxidants may be a balance issue, where too much of one side may be a problem7.
- Do antioxidants remain intact (and beneficial) through digestion?
What about Antioxidants in Skincare?
So the data on foods and nutrition are a bit murky, but what about antioxidants in skincare? None other than legendary beauty care critic Paula Begoun makes a point about antioxidants in formulations as one of the important criteria to look for on Beautypedia review. Secondly, assuming that antioxidants are good and desirable, will they work effectively, and how much? Here, the data seems less than spectacular. In addition to the murkiness of evidence that plaques antioxidants in foods, when applied topically, it presents some additional questions:
- Topical creams/lotions are applied to the skin's surface and come into contact with the oxygen, becoming oxidized immediately. It's unclear how much of it is absorbed into the dermis where the antioxidants will have an effect.
- How strong is the evidence for antioxidant efficacy when topically applied? How can this be isolated away from other factors and measured?8
- How long do they have to stay on the skin for?
- Does the formulation matter?9 (It does)
There's two types of evidence in question here. Is it likely that antioxidants are helpful? How efficacious is it? There seems to be mounting evidence that antioxidants are in fact helpful, both in foods, and in skincare products10. On the other hand, the evidence for how efficacious it is, seems lacking at this time. We don't really know, or at least are not able to measure in a consistent way, just how effective antioxidants are. Paula Begoun suggests that the presence of antioxidant ingredients is a plus (and mentions them in her reviews), but that consumers not expect the world from them either11. The practical solution as a consumer when the evidence is murky is to ask these questions.
- Can it harm me? Extremely unlikely. Although cosmetic products are not regulated effectively in terms of efficacy (they are not drugs), they are regulated in terms of safety.
- Is the product beneficial on its own merits? Most whole foods that contain helpings of antioxidants certainly qualify, as do evidence backed skincare products that also contain antioxidants.
- Is it worth the price? Only you can answer this question, but as the evidence becomes more concrete, you can adjust how much of a premium you are willing to pay for the antioxidant specifically.
5There's a wonderful article on just how murky the field of nutrition is from a statistical perspective: http://fivethirtyeight.com/features/you-cant-trust-what-you-read-about-nutrition/
6Certainly one can “overdose” from vitamin A (seal blubber, or excessive vitamins). Many nutrients don't have an upper limit recommendation as it is hard to naturally acquire so much, but with vitamins and supplements the game may change.
7Interesting read on maintaining homeostasis. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2952083/
8Sunburn cell assays can be used to measure the difference between skin that's been untreated, and one that has been treated with antioxidants. This appears crude, but it appears that this is the best we have. http://dermatologytimes.modernmedicine.com/dermatology-times/news/modernmedicine/modern-medicine-now/antioxidants-value-skincare-products-remai
9The antioxidant must stay active until it's actually applied to the skin. It also must be absorbed into the skin and at a high enough concentration to matter.
11This is a reasonable position, considering the evidence available. https://www.paulaschoice.com/expert-advice/skincare-advice/anti-aging-wrinkles/how-antioxidants-fight-the-signs-of-aging.html