December edition of American Spa magazine. By Gary Goldfaden, M.D
There is a key ingredient to healthy skin that is one of the most dynamic substances the human body produces. This vital substance has the power to activate more than 2,000 genes. It controls everything from normal bone growth and immune system response to healthy eyesight and neuromuscular function. It is absolutely essential to the long-lasting health and beauty of skin through its involvement in skin cell metabolism, growth, repair and protection. This largely overlooked nutrient is vitamin D.
A True Skin Saver
Every skin cell begins its life deep in the base layer of the epidermis. As these immature cells detach and migrate upward to the surface, they go through a series of complex changes in both form and function. The rate at which these cells divide, the nature and timing of their changes, as well as their transit time to the surface, are all controlled by growth factors and other molecules that are triggered by the presence of vitamin D. The skin loses and must replace about 40,000 cells every minute. If enough vitamin D is not available to fuel this process, replacement cells won’t be manufactured quickly enough. Inevitably, the outer layer of skin becomes thinner and more fragile and begins to sag from a lack of adequate support.
The skin has its own immune system that serves as the body’s first line of defense against bacteria, viruses, and other pathogens. When microorganisms attack, they secrete extracts that stimulate the production of vitamin D in the skin. The innate immune system responds by producing a substance called cathelicidin, a very powerful germicide that also helps promote the development of blood vessels and encourages new cell growth.
The skin is extremely susceptible to free radical damage because of its high metabolism and fatty acid content. Free radicals deteriorate the skin’s structural support and decrease its elasticity, resilience, and suppleness. The skin protects itself from this oxidative destruction through the presence of natural antioxidants. One of the most powerful of these is vitamin D.
A Modern Epidemic
The skin can synthesize approximately 10,000 IU of vitamin D after just 20 to 30 minutes of summer sun exposure. Unfortunately, between the ages of 20 and 70, about 75 percent of this ability to produce vitamin D is lost. In addition, today’s predominantly indoor lifestyle and widespread use of UV-blocking sunscreens have severely decreased the amount of vitamin D the average person produces.
Other limiting factors play a part as well. Darker skinned people need five to 10 times more exposure to synthesize the same amount of vitamin D as lighter skinned people. It is now estimated that roughly 75 percent of all teens and adults in the U.S. are vitamin D deficient. To make matters worse, most of the active vitamin D the body is able to produce is used to help build and maintain strong bones, not nurture the skin.
StormSister Two-Cents: We have almost gone off the deep-end in regard to sunscreen lately. I don't believe it needs to be applied daily, unless you work outside. If you are going to spend more than 30 minutes or longer in the sun, I don't find it necessary to apply it.
A bit of sunscreen applied to the face if you will be in bright sunlight for 15-20 minutes, is recommended though.