Many people around the world are not getting enough vitamin D, particularly during the winter months, and it’s having a major impact on their health. That is the opinion of one of the U.S.’s leading vitamin D experts, Michael Holick, M.D., and a group of other nutrition experts writing in the American Journal of Clinical Nutrition (March, 2007, 85(3);649-650.)

Their editorial, titled “The urgent need to recommend an intake of vitamin D that is effective,” says current recommended amounts of vitamin D are inadequate to address all the health problems now associated with vitamin D deficiency. The old recommendations don’t take into account new research showing higher amounts to be both safe and effective. Dr. Holick specifically calls for the recommended daily intake to be quadrupled-- to 800 IU/day of vitamin D. This would represent the minimum that one should take.

For many years, what was considered a “normal” blood level of vitamin D was a level that prevented osteomalacia or rickets--bone diseases caused by a vitamin D deficiency. But research now shows that much higher blood concentrations of vitamin D are necessary to prevent many health problems, including fractures, low bone density, colon cancer and tooth detachment.

Vitamin D insufficiency has also been found in people with chronic pain, fibromyalgia, chronic fatigue syndrome, depression, osteoarthritis, rheumatoid arthritis and multiple sclerosis, and may contribute to those problems, experts say. Vitamin D deficiency also seems to be related to insulin resistance, heart disease--even how long you live.

Some experts are also calling for the safe Upper Limit (UL) of vitamin D to be raised to 10,000 IU/day, from the current UL of 2,000 IU per day. (The Upper Limit does not constitute a recommended intake. It simply identifies a level of daily intake at which there is no known toxicity, and at which there is sufficient evidence of safety for a nutrient.)

Lots of people are at risk for vitamin D deficiency—older people, who make less vitamin D from sun exposure and who also tend to get less sun exposure, people with deeply pigmented skin, those using sunscreen, those with malabsorption, people taking anticonvulsants or drugs that inhibit cholesterol absorption, those getting treatment for AIDS, those with liver or kidney problems, and people who are obese. (Vitamin D is stored in fat tissue.)

To check your vitamin D status, your doctor can do a blood test to measure 25-hydroxyvitamin D, the primary circulating form of vitamin D in your body. Levels should be 30 ng/ml or higher. People with extremely low levels may have to take large amounts of vitamin D for some time to return to normal. Once they have attained normal levels, 1,000 IUs a day of vitamin D may be sufficient to keep your blood levels in a good range.
  
The Anti-Aging Bottom Line: Listen to what the experts are saying. Vitamin D deficiency has reached epidemic proportions in the U.S., and research has shown that you may need more vitamin D than was previously recommended to prevent symptoms of deficiency. Don't let low vitamin D levels undermine your health and well-being. Make sure you are getting at least 1,000 IU of supplemental vitamin D daily.

QUICK TIP: Getting adequate vitamin D may prevent or reverse some mood and memory problems. Learn More

RELATED PRODUCTS: Stop Aging Now has been tracking the calls for increased vitamin D levels for several years. In 2007, we made the decision to increase the levels in all of our multi-vitamins from 600 to 1,000 IU, at the recommendation of our board of scientific advisors and after consultation with the nation's leading experts.

Written exclusively for Stop Aging Now, the authority on anti-aging research, anti-aging nutrition, and anti-aging supplements.