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Information on the latest vitamin D news and research.

Find out more information on deficiency, supplementation, sun exposure, and how vitamin D relates to your health.

Newsletter: Racial differences in vitamin D status

Thomas Edison once said, “Opportunity is missed by most people because it is dressed in overalls and looks like work.” Politicians in Washington and scientists at the National Institutes of Health (NIH), the Institute of Medicine (IOM), and the Food and Drug Administration (FDA) have a rare opportunity, one dressed in the overalls of the advocacy group promoting it and requiring real scientific work to prove (or disprove). However, it may be the scientific, medical, and civil rights opportunity of a lifetime.

Most of us know that African Americans die at a younger age than whites due to a bewildering and seemingly disconnected array of diseases. Even ailments with a lower incidence among blacks, such as breast cancer, have a higher mortality in blacks. Why? Is it all socioeconomic factors? Or is there a near universal medical condition in the black community that is associated with virtually all the diseases that disparately and prematurely kill black Americans? Is there a single substance with a plausible mechanism of action that could parsimoniously explain virtually all the reasons African Americans die prematurely?

In the last four years, a number of studies have documented dramatic racial differences in the blood levels of a crucially important prehormone, 25-hydroxy vitamin D. These studies, when read in the context of clinical studies of vitamin D deficiency, offer scientists and physicians a unique opportunity to examine, and perhaps erase, some of the health inequities burdened by African Americans. Opportunities like these are rare in medical science (and in politics), but government officials, private citizens and the press must first be aware of the studies. What about you, how aware are you? How many of the following thirteen questions can you answer correctly?

1. Blacks are about ten times more likely to be vitamin D deficient than are whites.

A) true
B) false

The answer is true. Of course, it all depends on how you define vitamin D deficiency but the problem is much more severe in the black community. The reason is simple: humans get most of their vitamin D from the sun and blacks need up to ten times longer in the sun to produce the same amount of vitamin D as whites1, 2.

2. The incidence of vitamin D deficiency among black women of reproductive age is:

A) twice as high for blacks as whites
B) four times as high
C) ten times as high
D) twenty times as high

The answer is d, twenty times as high. Twelve percent of young black women had 25(OH)D levels below 20nm/L (8 ng/ml) while only 0.5% of whites had such levels3.

3. On the average, young white women of childbearing age have twice as much vitamin D in their blood as young black women.

A) true
B) false

The answer is true4.

4. The following diseases are:

A) associated with vitamin D deficiency.
B) more common among African Americans.
C) both.

• coronary heart disease
• hypertension
• type two diabetes
• colorectal cancer
• prostate cancer
• cervical cancer
• end stage renal disease
• metabolic syndrome
• multiple sclerosis
• rheumatoid conditions
• obesity
• periodontal disease
• rickets
• osteomalacia

The answer is both. With the exception of osteoporosis, the list of diseases associated with vitamin D deficiency and the list of diseases more common among African Americans are virtually identical. Osteoporosis, the exception that proves the rule, is a multifactorial disease whose main determinate is peak bone mass during puberty.

The law of parsimony (one explanation for multiple findings is better than multiple explanations for multiple findings) suggests the high rate of vitamin D deficiency among African Americans explains at least part of excessive disease and mortality among African Americans5, 6, 7, 8, 9, 10, 11, 12, 13.
Chronic Disease Epidemiology and Control, American Public Health Association, Second Edition, 1998

5. Vitamin D deficiency in African American mothers may explain the fact that black babies are more than twice as likely as whites to have low-birth-weights.

A) true
B) false

Dr. Kathleen Fuller, of the Center for the Study of Race and Ethnicity in Medicine at the University of Kansas School of Medicine was the first to point out this possibility14.

6. Eighty-three percent of American children diagnosed with vitamin D deficient rickets in the last 17 years were African Americans.

A) true
B) false

Again, true15.

7. Professor John McGrath recently documented that vitamin D is crucial for brain development.

A) true
B) false

Again, the answer is true. Low maternal vitamin D caused altered brain shape, reduced expression of nerve growth factors and increased cellular proliferation in the rat fetal brain. We don’t know what role it plays in humans. African Americans are certainly as intelligent as whites but that doesn’t mean all blacks fetuses (or all white fetuses) are in optimal intrauterine environments. However, another way of asking the question is: “Does it seem reasonable that the most potent steroid hormone in the human body may be important for optimal human brain development?”16

8. Breast milk of black women often has undetectable levels of vitamin D. With adequate supplementation, breast milk can easily be transformed into a rich source of vitamin D.

A) true
B) false

True. It is now clear that the reason most breast milk is such a poor source of vitamin D is because most mothers do not have enough vitamin D in their own blood to excrete it in their breast milk. Dr. Bruce Hollis and Dr. Carol Wagner recently solved an old and vexing medical question: Why is nature’s perfect food devoid of vitamin D? Answer: Because virtually all modern mothers are vitamin D deficient.

Hollis and Wagner found 4,000 units of cholecalciferol a day transformed vitamin D deficient lactating mothers into vitamin D replete lactating mothers whose breast milk transformed vitamin D deficient infants into vitamin D replete infants. The mothers needed 4,000 units a day, about as much vitamin D as whites get after about 5 minutes of full body summer sun exposure. Black women are much more likely to have undetectable levels of vitamin D in their breast milk than white mothers17, 18.

9. Blacks consume much less fresh milk than do whites

A) true
B) false

True, see below for discussion.

10. Under current FDA regulations, the only foods mandated to contain vitamin D are milk products.

A) true
B) false

The answer is true. Virtually all physicians know that blacks consume much less milk than whites; the most common reason given is that many blacks are lactose intolerant. The FDA delivers most of the vitamin D in supplemented food in the form of milk. I’m not saying, nor do I think, the FDA under the Bush administration continues to purposefully mandate only milk products be supplemented with vitamin D in order to hurt African Americans. I don’t know what Jesse Jackson, Al Sharpton or the NAACP would think.

However, the facts are upsetting and the facts are these:

  • African Americans are much more likely to be vitamin D deficient than whites
  • The only two foods the FDA mandates to contain vitamin D are milk products, (fortified nonfat dry milk and evaporated milk),
  • Virtually all the vitamin D in fortified food is delivered via milk,
  • African Americans consume little milk.

Foods which African Americans do consume in equal quantities, such as juice and cereals, may be supplemented with vitamin D but such fortification is not mandatory or widespread. Virtually all the vitamin D delivered to Americans via fortified food is delivered in fresh milk, a product that manufactures choose to fortify with vitamin D – a practice the FDA allows, but does not mandate unless the milk is advertised as vitamin D fortified milk. A recent study sponsored by the National Medical Association indicated blacks could consume more milk but choose not to do so for a variety of reasons. Unfortunately, there is usually no vitamin D in yogurt or cheese, foods African Americans do consume19, 20.

11. The FDA knows that vitamin D deficiency may explain a significant part of the excesses mortality in the black community.

A) true
B) false

True. In 2003, Dr. Mona Calvo, an FDA employee, wrote, “In sharp contrast to their white counterparts, blacks have a much higher incidence and mortality of certain types of aggressive cancers and autoimmune diseases, including diabetes that cannot be attributed entirely to socioeconomic differences or disparities in health care. The strong association between vitamin D insufficiency and risk of chronic diseases should raise concern about the current mechanisms in place to prevent [vitamin D deficiency].”21

12. The FDA also knows blacks do not drink much milk and are not getting as much supplemental vitamin D as whites.

A) true
B) false

True. In 2004, Dr. Calvo warned them again, “The racial/ethnicity groups at greatest risk of vitamin D insufficiency consume less milk . . . than do their white counterparts.” Dr. Calvo went on to say, “African Americans, with the greatest physiological need for dietary sources of vitamin D, have the lowest intake from food alone and food plus supplements.”22

13. When did we discover that vitamin D deficiency is much worse among African Americans and that the FDA’s food fortification program is shortchanging African Americans?

A) over the last twenty years
B) during the last four years.

The answer is b. Virtually all the studies were published in the last four years. That leaves the NIH, the IOM, the FDA, and the Bush Administration with a unique opportunity to right a wrong and, perhaps, do some real good. Opportunities like these are rare in medicine and rarer yet in politics. It may not look like an opportunity to many. After all, isn’t theory too simple and the solution too inexpensive to possibly be true? Mason Cooley once said, “Opportunity knocks, but doesn’t always answer to its name.”

  About: John Cannell, MD

Dr. John Cannell is founder of the Vitamin D Council. He has written many peer-reviewed papers on vitamin D and speaks frequently across the United States on the subject. Dr. Cannell holds an M.D. and has served the medical field as a general practitioner, emergency physician, and psychiatrist.