Institute of Medicine increases RDA for Vitamin D

The recommended dietary allowance for vitamin D in the USA and Canada have been increased - the guidelines were issued today by the Institute of Medicine (IoM). For the last ten years people have been reading conflicting reports on what their vitamin D intake should be, as well as calcium intake. Consequently, the US and Canadian governments asked the IoM to examine data and health outcomes linked to vitamin D and calcium consumption, and to produce new DRIs (Dietary Reference Intakes).

The new recommendations for daily vitamin D intake are (upper level):

• 1000 IU - infants up to 6 months of age
• 1,500 IU - ages 6 months to 12 months
• 2,500 IU - ages 1 to 3 years
• 3,000 IU - ages 4 to 8 years
• 4,000 IU - 9 years and older

The new recommendations for daily calcium intake are (upper level):

• 1,000 milligrams - infants up to 6 months of age
• 1,500 milligrams - ages 6 months to 12 months
• 2,500 milligrams - ages 1 to 8 years
• 3,000 milligrams - ages 9 to 18 years
• 2,500 milligrams - 19 years to 50
• 2,000 milligrams - 51 years and older

Vitamin D has historically been associated with healthy bones, however new research has revealed other benefits, including cancer and diabetes prevention. Vitamin D has also been found to reduce the risk of hypertension (high blood pressure).

Professor of foods and nutrition, James C. Fleet, from Purdue University, said:

"There is a consensus among most experts that many people have low serum of vitamin D levels, an indicator of vitamin D status, but there is disagreement on how high those levels need to be and how much is needed to raise vitamin D to a healthy level.

Some believe that vitamin D has incredible benefits and the recommended amount should be even higher than the new recommendation. However, research does not yet mirror those beliefs, so there is more work to be done."  Prof. Fleet studies how vitamin D controls calcium metabolism, as well as its role in prostate and colon cancer prevention. He adds that the new recommendations will help federal guidelines for various nutrition programs, including the food stamp program, the WIC (Woman, Infants and Children) program, and school lunch programs.

Vitamin D helps transport calcium and phosphorous through the digestive system - it is a cholecalciferol. Bone health does not only depend on adequate levels of calcium, but also phosphorous. Phosphorous is vital for cell strength and energy production.

Although sunlight is a good source of vitamin D, in that it stimulates the skin to synthesize the vitamin, it may also raise the risk of skin cancer. Sun exposure needs to be carefully measured, the amount depends on several factors, including which part of the world you live in, the season, and your type of skin. Some medications can also make the skin more sensitive to the negative effects of sunlight.

Prof. Fleet said:

"For most people, and assuming they live somewhere there is ample sunlight, it really doesn't take much sun to make adequate levels of vitamin D. However, that said, the dermatology community believes that there is no such thing as safe sun, so people need to get vitamin D from supplements or their diet."

Salmon, sardines, shrimp and eggs are rich in vitamin D. It is commonly added to breakfast cereals, orange juice and milk.

Fleet explains that most people do not consume enough vitamin D foods for their daily requirements. Vitamin supplements can be used to fill any dietary shortfalls.

People over 9 years of age should not receive over 4,000 IUs daily, Fleet adds. This is higher than the previous 2,000 limit. Those taking more than the recommended limit should check with their doctor.

Fleet said:  "Several groups need to especially pay attention to their vitamin D levels. For example, people with dark skin or those who cover up can't make vitamin D in their skin. Also, we lose the ability to make vitamin D in the skin as we age. At the same time, older adults' bones are becoming weaker, especially for postmenopausal women, so it is critical that vitamin D is consumed adequately to preserve bone health."

"Dietary Reference Intakes for Calcium and Vitamin D"

Source: Medical News Today / Christian Nordqvist