Antioxidants Slow Skin Aging
People over 45 years of age who eat antioxidant-rich foods appear to show slower skin aging
Time for wrinkles
Old age leads to a lot of changes in our bodies, many of which are not very desirable. Entering the realm of senescence requires sacrifice.
The extent of those changes is quite individual and depends on, among others, genetics, metabolism, lifestyle, and environment. Still, our immune function declines, the risk for cancer increases, it’s harder to keep/build muscle, bones become brittle, joints creak, memory is no longer what it used to be, and our microbiome and body shape change.
We start noticing wrinkles and our skin also becomes thinner (we shed skin cells all the time, and most old bodies can’t keep up with making new ones).
Part of this is simply exposure. More time on earth means more UV exposure, more contact with potentially abrasive chemicals, and so on. There are biological processes at play too. Fewer stem cells, as alluded to earlier, is one of those.
In the skin cells themselves, unwanted changes occur too. Inflammation increases and the production of certain transcription factors (proteins that control the expression of specific genes) goes down.
Still, the most important factor in skin aging is so-called photoaging, or exposure to UV rays. According to some estimates, this accounts for up to 80% of visible facial skin aging (note: the linked study looked only at Caucasian women, so the number might differ for other groups, but UV exposure is likely to be an important contributor regardless).
Food & Antioxidants
There is a lot of interest in the effect of dietary patterns on aging, but the effect of nutritional compounds on photoaging specifically is not widely studied.
Previous work hints that antioxidant supplements may be helpful, especially when they contain a combination of antioxidants. The reason is that UV rays can damage the skin cells’ DNA and the cellular ability to maintain a healthy, vibrant state. UV rays also oxidize molecules, which affects the skin’s structural integrity.
However, beyond supplements, there is something else that can contain a combination of antioxidants: food.
A new study investigates whether antioxidant-rich foods can mitigate UV-induced photoaging. Aka do fruits and vegetables keep your skin glowing? Intuitively we might say yes. And the study confirmed our hunch.
The participants (over 700 Australians of European ancestry, all <55 years of age at the start) had their skin assessed via microtopography (think a close-up picture) in 1992, 1996, and 2007. Their diets were evaluated through questionnaires taken in 1992, 1994, and 1996.
…those aged >45 years showed significantly less skin photoaging over time as dietary antioxidant capacity increased... Neither the inclusion of education, supplement use or BMI, use of time-varying sunscreen use, BMI or physical activity, and excluding current smokers nor restriction to participants with complete microtopography grades materially changed results.
They did not find the same in people younger than 45. That might be because younger people generally have less systemic oxidative stress.
…we and others found that the benefit of antioxidants from foods is more apparent in underlying conditions of oxidative stress, including chronological aging itself.
And for those interested, where did these Australians get their antioxidants?
Fruits, vegetables, juices, and nuts contributed 48% of total dietary antioxidant capacity, whereas 32% was contributed by tea (predominantly black tea), 10% by grain products, 5% by alcoholic drinks, and 4% by other foods.
Higher antioxidant intake was also correlated with higher fish and red wine consumption, but lower intakes of red meat, soft drinks, and beer.
Varied diets characterized by increasing antioxidant potential from foods may retard photoaging in older adults of European ancestry who are susceptible to sun damage and who have experienced moderate to high sun exposure. Further long-term studies are required to characterize the influence of foods on photoaging of the skin among younger adults and susceptible adults with lower levels of ambient sun exposure.
Of course, caveats:
- Fairly ethnically homogenous group. There’s no reason to suspect this finding will be very different in other ethnicities, but with this data, we can’t say either way.
- Antioxidants in food come packaged with a lot of other things, such as vitamins, fiber, and unsaturated fatty acids. As the authors themselves note:
…we found no association between the antioxidant potential of individual food groups and skin aging, suggesting that the beneficial effects of foods or nutrients result from the collective effects of all relevant food components
- Food questionnaires are notoriously tricky. Most people are not that good at recalling what they ate more than a few days ago. Some people even lie to make themselves look better. (Over a time period such as this, they might give you a clue about the overall dietary pattern, though. So not completely useless.)
- Finally, people who eat more fruit, vegetable, nuts, and other antioxidant-rich foods tend to have a healthier lifestyle as well. Healthy user bias? (But that was supposedly controlled for as much as possible.)
Still, to keep the wrinkles at bay, you could do worse than listen to the age-old parental adage: eat your fruits and vegetables.