|Vitamin D is an important vitamin which is deficient in over 80% of US adults. Vitamin D is found in only a few foods such as fish oil, fatty fish, eggs and vitamin D fortified milk. Vitamin D is also found in some forms of fish oil like cod liver oil. Vitamin D can also be produced from cholesterol in the body when the skin is exposed to ultraviolet light from sunshine. (Too much sun exposure can increase risk of skin cancer.)
|Many nutritional experts recommend that the US Recommended Daily Allowance for Vitamin D be increase from 400 international units per day to 800 international units per day. Vitamin D can become toxic if people consume over 100,000 international units per day over a long period of time.
Vitamin D plays a critical role in how bones utilize calcium and phosphorus. Lack of vitamin D in children can cause a bone deformity disease called Ricketts. Lack of Vitamin D in adults can lead to weakened bones or osteoporosis.
Vitamin D also plays a critical role in maintaining immunity. High levels of vitamin D consumption have been associated with significantly lower rates of many types of infection such as Tuberculosis. High levels of vitamin D has been associated with significantly lower rates of death among hospitalized patients and renal patients on kidney dialysis. Relatively high consumption of vitamin D is associated with significantly lower levels of many auto-immune diseases such as type 1 diabetes, psoriasis (a skin disease), rheumatoid arthritis, lupus, multiple sclerosis (MS) and inflammatory bowel disease (such as ulcerative coilitis and Crohn’s Disease). Various studies have also reported that patients with psoriasis, rheumatoid arthritis and inflammatory bowel disease improve when given a diet high in both vitamin D and omega 3.
I urge all readers to consume at least 800 international units of vitamin D daily. This is about the amount of vitamin D found in 2 teaspoons of cod liver oil. Cod liver oil is an especially useful supplement since it is high in both vitamin D and omega 3 fats. As noted earlier, most adults are deficient in both vitamin D and omega 3 fats.
A good recent review of the effects of vitamin D and immune health was written by Baeke et al and published in Current Opinion in Pharmacology 2010 In Press