Vitamin D Experts’ “Call to Action” Urges Major RDA Increase to 2000 IU

Anthony Norman, PhD – whose discoveries shape what is known today about vitamin D – has joined a group of 18 experts in urging the US government to increase its recommended daily vitamin D intake dramatically, to 2000 IU. At the same time they issued a joint statement “in support of the use of vitamin D for reducing incidence of several types of cancer, type 1 diabetes, and cardiovascular diseases.”

RIVERSIDE, Calif. – Increasingly, vitamin D is being recognized by several researchers as an important player in contributing to overall good health. Now a group of 18 vitamin D researchers at the University of California states that the recommended daily intake of the vitamin is inadequate, and asks the government to re-examine its recommendation.

Anthony Norman, a distinguished professor emeritus of biochemistry and of biomedical sciences at UC Riverside, is co-leading the UC group along with Cedric Garland, an adjunct professor of family and preventive medicine at UC San Diego, in its “call to action” recommending that the daily intake of vitamin D for adults be revised by the government to 2000 international units (IU).

Currently, the recommended daily intake of vitamin D is 200 IU for people up to 50 years old; 400 IU for people 51 to 70 years old; and 600 IU for people over 70 years old.

“The consensus among UC scientists who signed this statement is that 2000 IU per day of vitamin D3, a form of vitamin D, is the appropriate intake for most adult Americans,” said Norman, an international expert on vitamin D. “This intake is the National Academy of Sciences/Institute of Medicine’s upper limit for daily intake, and is 400 IU less than the National Academy of Sciences/Institute of Medicine’s ‘no adverse health effect’ level. Scientific concerns about this level of intake are minimal, based on the findings of the National Academy of Sciences.”

Norman explained that a 2000 IU daily intake of vitamin D can be achieved by a combination of sunshine, food, supplements, and possibly even limited tanning exposure.

“While more research on this topic is highly desirable, it should not delay recommending a 2000 IU daily intake of vitamin D for most people,” he said.

In its call to action, the group of 18 UC scientists, which includes researchers from the Riverside (3), Davis (3), Los Angeles (4), San Diego (5) and San Francisco (3) campuses, also issued a joint statement in support of the use of vitamin D for reducing incidence of several types of cancer, type 1 diabetes and cardiovascular diseases.

“Our consensus on vitamin D is intended to support public health action,” said Norman, who spoke for the group. “The amount of research that is currently available provides us enough information to release such a consensus at this time. The group of UC scientists is happy to endorse and support the advocacy organization, GrassrootsHealth ( in its newly launched ‘D*action’ Community Project. Its goals are coincident with the goals of the group of UC vitamin D researchers, namely, building awareness of the vitamin D deficiency problem and providing vitamin D testing as well as outcome evaluation of the results.”

On Dec. 2, Norman will participate in a seminar for health care professionals – “Diagnosis and Treatment of Vitamin D Deficiency” – being hosted by GrassrootsHealth at UC San Diego. Experts in cardiology, cancer, diabetes, bone and muscle health are scheduled to speak at the seminar.

“Continuing medical education credit is available to doctors and other professionals who participate in the seminar,” said Carole Baggerly, director of GrassrootsHealth.

• Because vitamin D is found in very few foods naturally, milk and other foods (often orange juice) are fortified with it. The fortification levels aim at about 400 IU per day.

• The vitamin is found in many dietary sources such as fish, eggs and cod liver oil, with the amounts per serving being generally about 400 IU.

• Exposure to the sun is a natural way of producing vitamin D in the body. But due to growing concerns about skin cancer and various lifestyle choices – spending time mostly indoors, wearing clothes that leave little skin exposed to sunlight, and living in high-latitude areas, especially in winters – people are not getting enough of the vitamin.

Norman stressed that several studies have reported substantial reductions in incidence of breast cancer, colon cancer and type 1 diabetes in association with adequate intake of vitamin D, the positive effect generally occurring within five years of initiation of adequate vitamin D intake.

He has been researching vitamin D for more than 45 years. In 1967, his laboratory discovered that the vitamin is converted into a steroid hormone by the body. Two years later, his laboratory discovered the vitamin D receptor (or VDR) – an essential receptor in more than 36 target organs of the body that respond biologically to the vitamin.

The December 2008 issue of the American Journal of Clinical Nutrition ( will feature an editorial by Norman on vitamin D in which he highlights the effect of ethnicity, sex, age, season, and pregnancy status on vitamin D status, and emphasizes that receptors in the immune, pancreas, heart-cardiovascular, muscle and brain systems in the body generate biological responses to vitamin D.

* * * *

Ed Note – For more information see also:

“Vitamin D a key player in overall health of several body organs, says UC Riverside biochemist”

The GrassrootsHealth Disease Incidence Prevention Chart showing required vitamin D serum 25(OH)D levels “for prevention of many diseases including cancers, falls, heart attacks and diabetes and several others.”

• The full text of Dr. Norman’s recent article, also published in the American Journal of Clinical Nutrition, “From vitamin D to hormone D: Fundamentals of the vitamin D endocrine system essential for good health.”

Note: This information has not been evaluated by the FDA. It is generic and is not meant to prevent, diagnose, treat or cure any illness, condition, or disease. It is very important that you make no change in your healthcare plan or health support regimen without researching and discussing it with your professional healthcare team.

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