An estimated one third of Americans aren't getting enough vitamin D—an essential compound that keeps your bones and immune system healthy. Recent studies also link vitamin D to lowering blood pressure, reducing cancer risks, warding off osteoporosis, and even preserving memory.
An organic compound, vitamin D is manufactured in the body when UVB rays mix with the 7-dehydrocholesterol. Vitamin D helps keep muscles and bones strong by maintaining the phosphorous and calcium levels in the blood. It also helps bones absorb calcium. A few minutes of sunlight a day is often sufficient for most people to produce enough vitamin D.
The Skin Cancer Foundation recommends 600 International Units of vitamin D daily for most of us—infants require less and seniors age 70 or older need 800 daily units, since it's harder for elderly people to synthesize vitamin D. People with darker skin need greater quantities of vitamin D than Caucasians. If you are obese, suffer from Inflammatory Bowel Disease, or live above 42 degrees north latitude (near the Canadian border), you should pay close attention to how much vitamin D you're taking in, since sunlight is likely not enough to produce the minimum your body needs.
The best way to supplement your vitamin D is through the foods you eat. Fortified milk, juice, and cereals are simple choices and popular options. An egg supplies 10 percent of your daily vitamin D intake. Oily fish like mackerel, herring, sardines, sockeye salmon, and fresh tuna are also great choices. Multivitamins often contain vitamin D. One of the best supplements—which supplies nearly four times the daily requirement—is cod liver oil.
The Skin Cancer Foundation strongly recommends that you meet your vitamin D needs through nutrition, rather than UV ray exposure. One of the arguments often made against sunscreen is that it blocks the skin's ability to create vitamin D, since it stops skin from absorbing UV rays. While this is true, the health benefits of sunscreen strongly outweigh the risks of UV exposure. And there are even studies that show that too much UV exposure can in fact break down your body's ability to synthesize vitamin D properly. Your best bet is to always wear sunscreen, steer clear of tanning beds, and eat a vitamin D-rich diet.
Sources:
Skincancer.org: "Make Vitamin D, Not UV, a Priority." Skin Cancer Foundation. Web. 2008
http://www.skincancer.org/healthy-lifestyle/vitamin-d/make-vitamin-d-not-uv-a-priority
Skincancer.org: "The Skin Cancer Foundation Statement on Obtaining Adequate Vitamin D." Skin Cancer Foundation. Web. 2011
http://www.skincancer.org/healthy-lifestyle/vitamin-d/the-skin-cancer-foundation-statement-on-obtaining-adequate-vitamin-d
