Soy products have anti-aging effects?
WHAT THEY’RE SAYING
Soy products such as soybeans, tofu, and soy milk may help to preserve skin-firming collagen and elastin which decline with age.
WHAT WE KNOW
Starting in our twenties, the properties of our skin that make it smooth and wrinkle-free—collagen and elastin—start to decline. For most women (and men too!) this is a scary thought! Millions of dollars are spent each year on cosmetic products and surgeries to slow down and sometimes reverse this process. As expression lines become more prominent, more serums and lotions are applied to preserve the image of youth.
The bad news is that the decrease in collagen and elastin—which gives your skin youthful radiance—is a natural, inevitable process of aging. The good news is that new research is predicting that soy foods can help to slow down this process! Edamame (soybeans), tofu, and soy milk contain isoflavones which are antioxidants that may protect the skin from damage caused from sun exposure.
HOW DO WE KNOW THIS?
A recent study published in Experimental Dermatology treated mouse and pig skins topically with soybean extracts. During the course of skin aging, elastin synthesis is reduced and elastase activity is accelerated—resulting in skin sagging and reduced skin elasticity. The study showed that soybean extracts promoted elastin activity and inhibited elastase activity. The study concluded that soybean extracts may be used as a skin care agent to reduce the signs of aging.¹
Another study in the Journal of the American College of Nutrition gave hairless mice soy extracts orally and irradiated them with UV light for four weeks. Mice treated with soy extract had a better appearance and less wrinkling than mice not given the soy extract. The study concluded that it appears that isoflavones (present in the soy products) had an anti-aging effect.²
Most of these current findings have been in animals, mainly mice, and therefore more research on the effects on humans needs to be done before any final conclusions can be made.
Isoflavones in soy products—which are antioxidants—are thought to attribute to anti-aging effects. However, all fruits and vegetables contain antioxidants that scavenge free radicals which are caused by many factors—including sun exposure. While more research (especially in humans) needs to be done to determine if soy products can decrease collagen and elastin deterioration, we do know that the antioxidants in fruits and vegetables protect against free radicals that can damage our tissues—including our skin tissues! Also, most fruits and vegetables are composed of a high percentage of water—and hydrated skin is healthy skin!
Remember that the aging process occurs internally in addition to the obvious external skin wrinkling. And fruits and vegetables give you the best recipe to help your body (inside and out) function its best through the years. So continue to eat a variety of fruits and vegetables each and every day to keep your body functioning optimally.
¹ Zhao, R, Et al. “Extracts from Glycine Max (soybean) Induced Elastin Synthesis and Inhibit Elastase Activity.” Experimental Dermatology (2009); 18(10): 882-6.
² Kim, SY, Et al. “Protective Effects of Dietary Soy Isoflavones Against UV-Induced Skin-Aging in Hairless Mouse Model.” Journal of the American College of Nutrition (2004); 23(2): 157-62.