Vitamin D deficiency is a global problem – Johns Hopkins News-Letter
As full-time students, most of us spend a lot of time indoors, and that could be hurting our health.
Vitamin D, one of the 13 vitamins our body needs, is in such deficient quantity in many of us that vitamin D deficiency is now considered a global health problem, affecting an estimated one billion people worldwide.
Vitamin D is a fat-soluble vitamin. Thus, excess is stored in our fat tissue, unlike water-soluble vitamins like vitamin C, excess of which is expelled through urine. You would think that this would help us to keep our vitamin D levels up to where they should be — with enough stored in our fat cells to use in times of need.
The problem is that vitamin D is naturally present in very few foods, such as the flesh of fatty fish such as salmon and tuna, as well as beef liver, cheese and egg yolks.
Fortified foods provide most of the vitamin D in the diets of Americans. Most milk sold in the U.S. is fortified with vitamin D. Companies began adding vitamin D to milk in the 1930s to prevent bone diseases such as rickets in children and osteomalacia in adults.
Another source of vitamin D is from the reaction the skin has to exposure to sunlight. So, if we don’t eat the proper foods, drink enough milk or get sufficient exposure to the sun, we are setting ourselves up for vitamin D deficiency.
Vitamins are considered essential nutrients because our bodies cannot make them, or they are made in very small amounts. What this means to people interested in their health is that they need to derive the proper amount of vitamins from the food that they consume, or in the case of vitamin D, proper food and sun exposure. Lacking the amount that our bodies need may result in diseases or other health problems.
Vitamin D promotes calcium absorption and maintains proper serum calcium levels to enable normal bone mineralization. Without the proper amount of vitamin D, bone can become brittle and thin. It is particularly important in older adults where, together with calcium, it helps protect against osteoporosis. Vitamin D also modulates cell growth, immune and neuromuscular function and the reduction of inflammation.
Serum concentration of 25(OH)D derived from a simple blood test is the best indicator of vitamin D status, according to the National Institutes of Health (NIH) Office of Dietary Supplements.
Recently, the proper amount of vitamin D intake has been brought into question. Researchers at UC San Diego and Creighton University have disputed the intake of vitamin D recommended by the National Academy of Sciences (NAS) Institute of Medicine (IOM), which provides dietary recommendations to the U.S. government.
The researchers believe that their findings suggest that the IOM has substantially underestimated how much vitamin D we should be getting.
The error has broad implications for public health with regards to disease prevention and achieving the stated goal of ensuring that the whole population has enough of the vitamin to maintain proper bone health.
The recommended intake of vitamin D specified by the IOM is 600 international units (IU) per day through age 70 and 800 IU per day for older individuals. The researchers said that their calculations have shown that these doses are only about one-tenth of those needed to cut the incidence of diseases related to vitamin D deficiency.
So, the next time you are soaking in the sun while studying on the Beach, and your friends walk by and question your commitment to your education, just tell them that you are studying hard and working on increasing your vitamin D level. And we could all use a little more sun.