Vitamin D deficiency is widespread. News agencies like the Washington Post and CNN report that 70 percent of American children do not get enough vitamin D and that low levels of this hormone-like nutrient are considered a major health risk. The role of vitamin D in overall health has only recently begun to be understood by medical professionals, who can now use simple blood tests to diagnose and monitor deficiency.
Avoiding UV Rays Contributes to Deficiency
Vitamin D3 is produced in the skin after exposure to sunlight, with dark-skinned individuals requiring more time in the sun for this process to occur. Early research shows that precursors to vitamin D synthesis are contained in natural oils on the skin’s surface and that bathing removes these. Most people in developed countries are in the habit of washing regularly. Those who are not opposed to waiting three days and only using soap on the parts that really need it, may increase the amount of vitamin D3 their body absorbs.
Vitamins D3 and D2 Differ by Origin
People and other animals synthesize D3. Vitamin D2 is produced commercially by the irradiation of yeast. Foods such as milk, orange juice and cereals are fortified with D2. Dietary sources of D3 include deep sea and fatty cold water fish. Small amounts are found in beef liver, egg yolks and cheese. Cod liver oil is a traditional remedy for vitamin D deficiency.
Vitamin D Aids Cardiovascular Health
Acting as a hormone, the sunshine vitamin suppresses the release of renin by the kidneys. Renin triggers angiotensin in order to narrow blood vessels and raise blood pressure. The effect also stimulates the adrenal glands to secrete aldosterone, a hormone that causes the body to retain sodium and fluids. High blood pressure can damage arteries over time. Vitamin D is thought to reduce inflammation, protecting blood vessels.
Sunshine Affects Bone Health, Too
Prior to milk fortification in the United States, children frequently developed rickets from vitamin D deficiency. The bowed legs, curved spine and protruding breastbone characteristic of rickets is seldom seen today. But older adults, particularly elderly women, still suffer from bone loss that leads to falls and fractures, due in large part to vitamin D insufficiency. The sunshine vitamin is responsible for regulating calcium. When the body needs more of this mineral, vitamin D increases the absorption of calcium from foods in the digestive tract. If there are not enough calcium-rich foods, such as fish and green leafy vegetables, the bones de-mineralize, releasing calcium into the bloodstream. This process maintains the electrolyte balance of cells, a source of strength in muscles and essential for cardiac function. Symptoms of vitamin D deficiency may include muscle weakness, bone pain, and irregular heartbeat.
Pancreatic Function and the Immune System Rely on Vitamin D
A review of studies by the Mayo Clinic found evidence that pancreatic function may be compromised by vitamin D deficiency. The sunshine vitamin seems to bolster immunity and protect insulin-secreting beta cells, preventing the development of type 1 diabetes. Vitamin D also protects against insulin resistance, which is characteristic of type 2 diabetes. People with adequate levels of vitamin D may also have fewer and milder colds and flu.
Vitamin D Plays a Role in Mood and Memory
The sunshine vitamin is important for normal brain function. Studies analyzed by the Mayo Clinic demonstrate that among people in similar circumstances, those with lower vitamin D levels suffer more episodes of depression. Better memory and learning in older adults is also associated with higher levels of vitamin D, and vitamin D deficiency may increase the risk of developing schizophrenia, at least in men.
Numerous Other Health Conditions May Benefit From Increased Vitamin D Levels
The Mayo Clinic research includes findings that link low levels of vitamin D during pregnancy to childhood asthma. Vitamin D supplements may be therapeutic in the treatment of multiple sclerosis. The sunshine vitamin may also protect against vision loss from age-related macular degeneration in older adults, and animal studies indicate high levels of vitamin D may reduced the risk of some cancers.
Testing and treatment for vitamin D deficiency is safe, simple and affordable. Because adequate levels of vitamin D are associated with disease prevention and amelioration, safeguarding health in this way makes good sense.
Sources:
CNN Health, "Vitamin D Deficiency Common in U.S. Children," accessed April 17, 2011
The Washington Post, "Vitamin D Deficiency Called Major Health Risk," accessed April 17, 2011
Studies Inst. Divi Thomae, Vitamin D Precursors Removed From the Skin by Washing, Helmer AC, Jensen CH. 1937, 1
Mayo Clinic Proceedings, Vitamin D Insufficiency, Thatcher, T., Clarke, B., December 30, 2010, 86(1)
Disclaimer: The information contained in this article is for educational purposes only and should not be used for diagnosis or to guide treatment without the opinion of a health professional. Any reader who is concerned about his or her health should contact a doctor for advice.
Mary Earhart - Mary Earhart, RN, BSN, is a Licensed Midwife. She has written articles for professional journals and grants for non-profit agencies as ...
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