Skin and Diet
by Katta MD
Eat Power: The Scientific Basis
How do these powerful foods work to help the skin?
KEY POINTS:
1. Dietary antioxidants have been shown to combat the cellular damage inflicted by UV radiation.
2. Eating "power" carbs instead of refined carbs helps your skin in several ways.
3. Eating "power" fats may help your skin barrier function.
4. Anti-glycation foods: Research suggests that certain foods may actually help protect our collagen.
5. Eating probiotic foods may help the skin.
6. Prebiotic foods encourage the growth of "good" bacteria in our gut.
1. Dietary antioxidants have been shown to combat the cellular damage inflicted by UV radiation.
Certain foods can combat the damage inflicted by UV radiation. This damage is known as photoaging. We know that chronic sun exposure, over years, changes the skin in fundamental ways. The damage inflicted by UV radiation can ultimately lead to fine lines and wrinkles, freckling and sun spots, loss of elasticity, and thinning of the skin.
Research has shown that certain antioxidants that are provided via our diet can actually prevent, on a molecular level, some of the damage inflicted by UV radiation. For example, tomato paste given before exposure to UV radiation actually limited the sunburn response. A sunburn is the outward sign of cellular damage, and in one study, subjects who ate about 2 tablespoons of tomato paste daily for 10 weeks showed less of a sunburn response after being exposed to UV radiation. This isn't the same as sunscreen, of course, but it adds an extra level of protection against the damaging effects of the sun's rays.
Foods like tomatoes are rich in antioxidants, which can combat UV damage.
Researchers have been very interested to see if the antioxidants present naturally in certain foods can combat the damage from UV radiation. In laboratory studies, animal studies, and even in some human studies, these antioxidants have shown significant promise. They are able to block, or even repair, some of the cellular damage caused by UV radiation. Some antioxidants neutralize reactive oxygen species [which cause skin damage], while some antioxidants can actually increase the body's production of DNA repair enzymes.
What are some of the foods that are high in dietary antioxidants?
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Resveratrol in red grapes
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Lycopene in tomatoes and tomato paste
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Ellagic acid in raspberries
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Polyphenols in green tea
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Curcumin in turmeric
This is a very limited list. There are probably thousands more antioxidants present in fruits, vegetables, spices, herbs, seeds, and nuts.
Why do we emphasize the intake of foods rather than just recommending an antioxidant pill? Because the studies that have tested supplements containing isolated antioxidants have shown that they just don't work the same way as the antioxidants supplied in foods. Researchers aren't sure why this is, but I believe it's that whole foods provide fiber and many other phytonutrients, and that the synergy of these substances promotes their beneficial effects. [Synergy means that substances acting together are more powerful than those substances acting alone, and this has been demonstrated in multiple laboratory studies.]
Lentils, beans, and whole grains are power carbs containing several powerful nutrients that can help your skin.
2. Eating "power" carbs instead of refined carbs helps your skin in several ways.
Why do I consider lentils, beans, and whole grains to be power carbs? It's because these foods are a great source of several powerful nutrients.
Consuming power carbs in place of refined carbs [such as white bread and white rice], can help your skin in several ways.
1. Power carbs are a surprising source of powerful antioxidants. Beans, for example, provide selenium, a mineral that's been shown to help fight oxidation. In laboratory and animal studies, selenium has even helped to reduce the incidence of skin cancer. That's only one nutrient. In fact, there are many other phytonutrients found in beans and lentils, and researchers have only just started to uncover their many benefits.
2. Power carbs provide a hefty dose of fiber. Fiber is considered to be an incredibly important nutrient, even though we don't always hear that message. We hear celebrities talk about eating more protein, and we've all been told to make sure we're getting enough vitamins and minerals. The message of "eat more fiber" isn't as popular, but it's incredibly important for our health and our skin. [and I'm talking real, food-based fiber, like the type you find in beans and vegetables. The fake fiber that's added to protein bars and protein shakes hasn't yet been shown to function in the body in the same way as real fiber, so I'm leery of relying on fake fiber for health benefits.]
Researchers are still discovering the amazing properties of fiber. From a skin standpoint, foods that naturally contain higher levels of fiber help to stabilize blood sugar, which in turn helps protect our collagen.
The fiber found in certain vegetables also acts as a prebiotic. Prebiotics are substances that act to promote the growth of "good bacteria" in our gut, which may help tame certain inflammatory skin conditions.
3. The carbohydrates in beans, lentils, and certain whole grains come with a hefty dose of fiber and protein. These help stabilize blood sugar, which in turn helps preserve collagen [as described in the next section].
3. Eating "power" fats may help your skin barrier function.
What about the loss of moisture that occurs as we age? It's possible that consuming more monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) can help. These "good" fats also have anti-inflammatory properties, which may also help preserve our skin. In one study, flaxseed oil was given to volunteers with sensitive skin. After 12 weeks of daily consumption, the volunteers showed less irritation after exposure to an irritating substance. They also demonstrated less transepidermal water loss, which means their skin held on to moisture better. Their skin even exhibited less roughness.
What are some examples of power fats? A few examples of foods that supply fats and powerful nutrients include nuts [walnuts, Brazil nuts, almonds, pecans], seeds [chia seeds, ground flaxseeds], avocados, and fatty fish [such as salmon].
4. Anti-glycation foods: Research suggests that certain foods may actually help protect our collagen.
In the next section, I discuss glycation, a process that alters our youthful collagen. This process occurs in the presence of higher blood sugars. These higher blood sugars result in changes to the collagen and elastin fibers in the skin, which results in the formation of advanced glycation end products. These are [fittingly] referred to as AGEs. Over time, these changes in the collagen and elastin fibers manifest as wrinkling and sagging of the skin, a process I refer to as sugar sag.
While controlling your blood sugar is important step in preventing sugar sag, eating more of certain foods can help also. This is because certain foods have actually been shown to help combat the production of AGEs or help reduce the damage caused by AGEs.
In laboratory studies, several herbs and spices have helped to reduce the production of AGES. These have included cinnamon, cloves, oregano, and allspice. Other dietary compounds that have helped to reduce AGE formation include ginger, garlic, and green tea catechins, among others.
Dietary antioxidants may also help limit the tissue damage caused by AGEs, which is yet another reason to eat more foods that are naturally high in antioxidants.
5. Eating probiotic foods may help the skin.
Research suggests that probiotic foods may be good for the skin. "Probiotics" refers to foods or supplements that contain live active cultures of "good" bacteria and other microbes. Research has already shown that these may be helpful for some persons with eczema, a skin condition that results in sensitive skin and itchy red patches on the skin. There's even a suggestion that probiotics may be helpful for some persons with acne and rosacea.
6. Prebiotic foods encourage the growth of "good" bacteria in our gut.
The fiber found in certain vegetables acts as a prebiotic. That means it helps encourage the growth of "good" bacteria in our gut, which may help with certain inflammatory conditions of the skin. Some studies have found that consuming more synbiotics, which are combinations of probiotics with prebiotics, helps improve the skin of certain patients with eczema.
