CDC Study Shows Women, Blacks, and Hispanics Don't Get Enough Iodine, Iron, or Vitamin D
April 2, 2012 -- Most Americans are getting recommended amounts of vitamins, iron, and other essential elements in their diets, but women and some racial and ethnic groups may be low in certain key nutrients, a new government report shows.
The new report, from the CDC, measured 58 essential nutrients -- including vitamins, iron, folate, and iodine -- in the blood and urine of thousands of people who are participating in the ongoing National Health and Nutrition Examination Survey (NHANES) at two different time points, from 1999 to 2002 and from 2003 to 2006.
Less than 10% of people in the study had any nutritional deficiencies.
When researchers narrowed their focus, however, they did find some trouble spots.
“The highest deficiencies we found were for vitamin D,” says researcher Christine M. Pfeiffer, PhD, chief of the nutritional biomarkers branch at the CDC.
Vitamin D is found in fortified dairy products and fatty fish, but few of us get enough D from these sources alone.
Instead, most vitamin D comes from sunlight after it’s processed by the skin. The CDC study found that nearly one-third of African-Americans and 12% of Hispanics have levels of vitamin D that are considered low by scientific standards, compared to 3% of whites.
Whether that’s a problem or simply the result of a one-size-fits-all standard is a matter of debate.
Blacks and Hispanics have lower rates of osteoporosis than whites do, leading experts to wonder if everyone needs the same level of vitamin D.
“Blacks have better bone health, less fractures, stronger bone. It’s interesting to see that they can maintain that, the good bone health, even though they have much lower levels than the other groups,” Pfeiffer says.
Iodine deficiency, a problem that hasn’t been widespread in the U.S. since the 1920s, when the element was first added to table salt, may be making a comeback.
As a group, women between the ages of 20 and 49 appear to have iodine levels so low they border on deficiency.