Vitamin D promises to be the most talked-about and written-about supplement of the decade. While studies continue to refine optimal blood levels and recommended dietary amounts, the fact remains that a huge part of the population — from robust newborns to the frail elderly, and many others in between — are deficient in this essential nutrient.
If the findings of existing clinical trials hold up in future research, the potential consequences of this deficiency are likely to go far beyond inadequate bone development and excessive bone loss that can result in falls and fractures. Every tissue in the body, including the brain, heart, muscles and immune system, has receptors for vitamin D, meaning that this nutrient is needed at proper levels for these tissues to function well.
Studies indicate that the effects of a vitamin D deficiency include an elevated risk of developing (and dying from) cancers of the colon, breast and prostate; high blood pressure and cardiovascular disease; osteoarthritis; and immune-system abnormalities that can result in infections and autoimmune disorders like multiple sclerosis, Type 1 diabetes and rheumatoid arthritis.
Most people in the modern world have lifestyles that prevent them from acquiring the levels of vitamin D that evolution intended us to have. The sun’s ultraviolet-B rays absorbed through the skin are the body’s main source of this nutrient. Early humans evolved near the equator, where sun exposure is intense year round, and minimally clothed people spent most of the day outdoors…
Although more foods today are supplemented with vitamin D, experts say it is rarely possible to consume adequate amounts through foods. The main dietary sources are wild-caught oily fish (salmon, mackerel, bluefish, and canned tuna) and fortified milk and baby formula, cereal and orange juice.
People in colder regions form their year’s supply of natural vitamin D in summer, when ultraviolet-B rays are most direct. But the less sun exposure, the darker a person’s skin and the more sunscreen used, the less previtamin D is formed and the lower the serum levels of the vitamin. People who are sun-phobic, babies who are exclusively breast-fed, the elderly and those living in nursing homes are particularly at risk of a serious vitamin D deficiency.
An article well worth reading. Lots of detail. Lots of sound, sensible science-based recommendations.
If you’re lazy, experts recommend that adults take a daily supplement of 1,000 to 2,000 units. You need to know that much.
Yes, I do.