VITAMIN D, ITS SOURCES AND BENEFITS

Vitamin D, also referred to as calciferol, is a fat-soluble vitamin that is naturally present in some foods, added to others, and is also available as a dietary supplement. It is also produced endogenously when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis.

Many people may not be meeting the minimum requirement for vitamin D. The Recommended Dietary Allowance for vitamin D provides the daily amount needed to maintain healthy bones and normal calcium metabolism in healthy people. It assumes minimal sun exposure. The Recommended Dietary Allowance for adults 19 years and older is 15 mcg daily for men and women, and for adults over 70 years it is 20 mcg daily.

Some foods are naturally rich in vitamin D3. The best sources are the flesh of fatty fish and fish liver oils. Smaller amounts are found in egg yolks, cheese, and beef liver. A few mushrooms contain some vitamin D2. In addition some commercially sold mushrooms contain higher amounts of D2 due to intentionally being exposed to high amounts of ultraviolet light. Many foods and supplements are fortified with vitamin D like dairy products and cereals.

Vitamin D is not just one vitamin. It’s a family of nutrients that shares similarities in chemical structure. In our diet, the most commonly found members are vitamin D2 and D3. While both types help us meet our vitamin D requirements, they differ in a some important ways. Research even suggests that vitamin D2 is less effective than vitamin D3 at raising blood levels of vitamin D. Vitamin D2 is made from plants and is found in fortified foods and some supplements. Vitamin D3 is naturally produced in the human body and is found in animal foods.

Vitamin D deficiency may occur from a lack in the diet, poor absorption, or having a metabolic need for higher amounts. If one is not eating enough vitamin D and does not receive enough ultraviolet sun exposure over an extended period, a deficiency may arise. People who cannot tolerate or do not eat milk, eggs, and fish, such as those with a lactose intolerance or who follow a vegan diet, are at higher risk for a deficiency.

Vitamin D helps in regulating the amount of calcium and phosphate in the body. Our bodies need these nutrients to keep bones, teeth and muscles healthy. A lack of vitamin D can lead to bone deformities such as rickets in children, and bone pain caused by a condition called osteomalacia in adults.