Vitamin D can’t be metabolized without sufficient magnesium levels. Thus, it remains stored and inactive for as many as 50 percent of Americans on nutrient-poor diets, reports a research review in the Journal of the American Osteopathic Association. “Without magnesium, vitamin D is not really useful or safe,” says study co-author Mohammed S. Razzaque, Ph.D., a professor of pathology at Lake Erie College of Osteopathic Medicine, in Erie, Pennsylvania.

As a consequence, taking vitamin D supplements can increase a person’s calcium and phosphate levels, even if they remain vitamin D deficient, he explains; and that can lead to vascular calcification if their magnesium levels aren’t sufficient.

The magnesium factor may explain why vitamin D supplementation doesn’t necessarily help vitamin D deficiency-related disorders such as skeletal deformities, cardiovascular diseases and metabolic syndrome. Natural sources of magnesium include almonds, cashews and other nuts, bananas, beans, broccoli, brown rice, egg yolks, fish oil, green vegetables, mushrooms, oatmeal, soybeans, sweet corn, tofu, whole grains, and pumpkin, sesame, sunflower and flax seeds.

 

Image: Tang Yan Song/Shutterstock.com