Summer Sun Helps Reverse Winter Vitamin D Deficiency

One recent study referred to vitamin D deficiency as “a major unrecognized epidemic in the older adult population” and recommended routine blood testing for adequate levels.

Open to speculation, Drake says, is that deficiencies of vitamin D may have worsened in recent years as more people became aware of the risks of skin cancer and aggressively avoided sun exposure or used sunscreen lotions, on themselves and their children. Experts still agree that a fairly modest amount of sun is enough—perhaps 10-15 minutes of exposure on your arms and face about three times a week. Sunburn should of course be avoided.

Alternatively, you also can get vitamin D from some foods, including vitamin fortified milk and some cereals or breads—assuming you don’t have a diet rich in oily fish. For higher levels, supplements are usually necessary.

Among the recent findings and observations about vitamin D:

• Vitamin D is a fat-soluble vitamin that functions as a hormone in the body, regulating calcium metabolism.
• Most people living above 40 degrees latitude do not obtain enough vitamin D from about mid-November to early March.
• Infants who are exclusively breast-fed, and are not supplemented with vitamin D, are at high risk of vitamin D deficiency, because human milk generally doesn’t have adequate levels.
• People with dark-colored skin have significantly less ability to synthesize vitamin D from sunlight, as do the elderly.
• Obesity increases the risk of vitamin D deficiency because obese individuals cannot easily access the vitamin D stored in body fat.

So if adequate levels of vitamin D are critical to your health, how much is enough? Depends on who you ask, Drake says. The official government recommendation is 200 IU per day—although moderate sun exposure might provide about 100 times that much. Many multivitamins provide about 400 IU per day, and it’s generally accepted that levels up to 2,000 IU per day pose no health risk. Some studies underway with pregnant women are giving them 4,000 IU per day in supplements.

One study last year indicated an adequate level of vitamin D, produced by daily supplements of up to 2,000 IU per day, might prevent 30 percent of breast cancer cases and 50 percent of colon cancer cases in the United States—at extremely low cost and with few or no adverse effects.

The Linus Pauling Institute recommends a multivitamin supplement with at least 400 IU of vitamin D for most healthy adults, and twice that amount for anyone over age 50. Additionally, at least 10-15 minutes of sun exposure on the arms and legs, or face and arms, at least three times weekly, between 11 a.m. and 2 p.m. during the spring, summer and fall may help residents of temperate latitudes avoid vitamin D deficiency at the end of winter.

“There’s a lot we still have to learn about this micronutrient, but it’s already clear the role it has in optimal health, and that a lot of people don’t get enough,” Drake says. “Many people may need to consider supplements, especially in winter. And one thing we would say is, don’t be afraid of getting at least a little sunshine. It’s good for you.”

Source: PhysOrg.com