Describing vitamin D deficiency as a ‘daunting problem’ in the 21st Century, researchers may have found a good way to fortify bread as well as milk.
On a global level, most people are unable to get enough vitamin D from sunlight or foods, explains Connie Weaver, PhD, a researcher in the Department of Foods & Nutrition at Purdue University.
“On average, Americans consume only one-third of the recommended intakes for vitamin D, which enables the body to absorb calcium,” she says. And new research shows that, “far from just contributing to healthy bones, vitamin D seems to have body-wide beneficial effects. Vitamin D insufficiency has been linked to an increased risk of heart disease, cancer, allergy in children, and other conditions.”
However, she points out,“with few good natural sources of vitamin D, milk producers long have added it to milk, but dairy products just don’t provide enough. The body makes its own vitamin D when the skin is exposed to sunlight. But people are not exposed to sun in winter and are avoiding the sun and using sun blocks in summer. So we have been looking for new ways to add vitamin D to the diet.”
Adding high levels of vitamin D to baked bread has seemed like the answer to the problem, but some scientists have been skeptical. So the Purdue team conducted a study using growing, D-deficient lab animals as stand-ins for humans, and feeding them bread made with UV-irradiated yeast - with interesting results. Their study, confirming that the approach works in laboratory tests, is
reported in the Journal of Agricultural and Food Chemistry.
“The doubts originated because yeast produces one form of the vitamin, termed vitamin D2, which has been thought to be not as biologically active as the form produced by sun, vitamin D3,”* Dr. Weaver says. “But our study showed that bread made with vitamin D2-rich yeast, fed to the laboratory rats, had effects that seemed just as beneficial as vitamin D3. These results suggest that bread made with high vitamin D yeast could be a valuable new source of vitamin D in the diet.”
* Note: Plants manufacture vitamin D2; and the human body - requiring biologically active D3 - has the options of transforming some D2 derived from foods to D3, manufacturing D3 directly from exposure to sunlight, and/or deriving D3 from a supplement.
Source: American Chemical Society news release, Apr 18, 2011