A surprising number of Americans have lower than optimum levels of vitamin D due, in recent decades, to fewer outdoor activities and more use of sunscreen. Only a small percentage of the sunshine vitamin is absorbed from the foods we eat and that leaves many of us with inadequate levels and completely unaware. Vitamin D levels also tend to be harder to maintain in the elderly, in the obese, in people who have dark skin, and during winter months.
A study of childbearing women in the northern U.S. found inadequate levels of vitamin D in 54% of black women and 42% of white women. If you spend most of your time indoors and use sunscreen when you go out, you may also be deficient in vitamin D.
Low levels of vitamin D have recently been associated with increased risk of death from cardiovascular disease, increased risk of some cancers, cognitive decline in older people, a weaker immune system, depression, and higher risk of diabetes and osteoporosis.. Extreme vitamin D deficiency can cause rickets, a condition in which the bones are too soft and create skeletal deformities
Vitamin D has been getting more attention lately for its important role in the body. It has been found to aid in the absorption of calcium and build strong bones, improve dental health, play a strong role in the body’s immune system, reduce inflammation and possibly offer some protection against arthritis and some cancers. A 2007 study showed that people taking vitamin D supplements were 7% less likely to die than those who didn’t take supplements.
Dietary sources of vitamin D include salmon, tuna, sardines, mackerel, shrimp, egg yolks, mushrooms, and fortified milk and cereals. Sunlight on the skin is the best source of vitamin D. John Jacob Cannell, MD, executive director of The Vitamin D Council, claims that the skin can make 10,000 IU of vitamin D after 30 minutes of full-body sun exposure. Of course this can vary with time of year, climate zone, age of person, and darkness of skin.
Overdosing on vitamin D from sun exposure or from food is extremely unlikely. Most vitamin D overdoses come from supplements and, according to WebMD, too much vitamin D can cause an abnormally high blood calcium level, which could lead to confusion, nausea, constipation, abnormal heart rhythm, and even kidney stones.
Vitamin D is fat soluble and levels take time to build up or decrease in the body. Before you rush out and buy a bottle of vitamin D softgels, a simple blood test will reveal your level and your doctor can advise whether or not you should, in fact, take vitamin D supplements. The medical community has not agreed on specific recommended daily doses of vitamin D but more information is available in the above videos.
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