Part 1
Recently I was honored to join
Professors David Sinclair of Harvard and Joseph Vercauteren of the University
of Montpelleir at an anti-aging symposium at the invitation of Mathilde Thomas
of Caudalie in Paris. Caudalie has been using wine extracts (and specifically
resveratrol) in their products for more than 15 years, after Vercauteren
identified it in wine grape vines. Sinclair has become well known for his work
identifying the role of sirtuin (SIRT) genes in anti-aging, and resveratrol as
a natural sirtuin activator. While much remains to be proven, it is fair to say
that science is finally beginning to have an impact on skin care. With an
increasing understanding of what causes aging in skin cells and how botanical
antioxidants such as resveratrol work at a molecular level, there is no excuse
to use anti-aging skin care products that don’t multitask.
Before delving into the potential
benefits of resveratrol in skin care, it may help to review how resveratrol
came into the spotlight in the first place. By just about any measure, moderate
wine consumption is among the most potent anti-aging lifestyle habits known.
And although resveratrol is present in only small amounts in wine, it is the
best known source; coupled with an impressive array of anti-aging properties
identified in laboratory conditions, resveratrol has been offered as the
mediator of wine’s benefits. Sales of resveratrol supplements have soared. (One
study noted that 2/3 of people who take supplements include resveratrol.)
Wine drinkers do enjoy healthier
skin. For example, a study from Australia (where skin damage from sun exposure
is a big deal) found that wine drinkers had a 27% lower risk of developing
premalignant lesions known as actinic keratoses (AK’s.) Another study, from
Germany, found that wine consumption – but not topical application of wine to
the skin – reduced the redness from controlled exposure to UV light; in other
words, a sunscreen you can drink.
From here the picture gets a bit
more complicated, so bear with me for a moment. Topically applied resveratrol
confers protection against damage from UV light in skin, just as it
provides a handy explanation for why wine drinkers have healthier hearts and brains,
and live longer. But remember that there isn’t enough resveratrol in wine to
produce the effects seen under lab conditions without consuming enormous
amounts, and supplements of resveratrol have a problem with what is known as “bioavailability.” That means that enough
of it has to be absorbed into the circulation and distributed to the target
tissue (in our case, skin) before being metabolized. Our digestive systems are
pretty efficient at disposing of resveratrol (or at least metabolizing it into
other compounds), and there is a high degree of variability between people.
To make matters even more confused,
there is the issue of a phenomenon known as hormesis.
This refers to paradoxical effects from the same thing in different amounts.
Resveratrol has demonstrated hormesis in several cancer types wherein it
promotes growth at low levels but inhibits at higher ones; the opposite may
occur with Alzheimer’s and osteoporosis. Balancing these opposing effects is a
considerable challenge, even if predictable levels of resveratrol in target
tissues could be achieved.
The upshot is that if you are
looking for the effects of resveratrol in the skin, it may be best to just put
it there in the first place. Fortunately, there is good evidence that resveratrol
is absorbed into the skin when applied topically. In Part 2 of this post I will
detail the ways in which resveratrol functions as the ideal anti-aging skin
care ingredient.
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