Postmenopausal and Depressed? Eat More Foods with Vitamin D
Postmenopausal women may find some relief from depression when they increase their intake of foods containing vitamin D, according to a new study published in the American Journal of Clinical Nutrition. Benefits from vitamin D supplements, however, do not appear to be as impressive.
Vitamin D is linked with several health benefits
Vitamin D is a popular focus of research, with some recent studies associating it with improving gum and teeth as well as reducing the risk of Parkinson’s disease, type 2 diabetes, skin cancer, and multiple sclerosis. Few studies have explored the role of the nutrient in depression.
This latest study involved 81,189 women who participated in the Women’s Health Initiative (WHI) Observational Study. The WHI was a major, 15-year program that looked at cardiovascular disease, cancer, and osteoporosis in postmenopausal women. Although probably best known for its look at hormone replacement therapy, the wealth of data gathered from the participants has allowed researchers to apply it for other purposes.
In this case, investigators from the University of Massachusetts, Amherst, looked at data on vitamin D intake from foods and supplements, as well as depressive symptoms over three years and antidepressant medication use. The researchers allowed for factors such as age, physical activity, and others.
Generally, the prevalence of depressive symptoms among women who had a total intake of at least 800 IU vitamin D daily was 21 percent lower than among women who got less than 100 IU vitamin D daily. When the researchers focused only on women who were depression-free at baseline, they found that women whose intake of vitamin D was at least 400 IU from food had a 20 percent lower risk of depressive symptoms at year 3 than did women who got less than 100 IU vitamin D from food.
Getting a sufficient amount of vitamin D from foods can be a challenge, as the list of excellent or very good sources is limited. Figures from the Office of Dietary Supplements report that 3 ounces of sockeye salmon provide about 450 IU, with 3 ounces of mackerel coming in under 400 IU and 3 ounces of canned tuna providing even less than half that amount. One cup of either fortified orange juice or milk supplies approximately 120 to 140 IU per serving, while servings of yogurt, beef liver, eggs, fortified cereals, and sardines all provide less than 100 IU.
According to JoAnn Manson, professor of epidemiology at Harvard School of Public Health, who led the study, the benefits from vitamin D supplements provided “less consistent” results. The authors concluded that “overall, our findings support a potential inverse association of vitamin D, primarily from food sources, and depressive symptoms in postmenopausal women.”
Bertone-Johnson ER et al. Vitamin D intake from foods and supplements and depressive symptoms in a diverse population of older women. American Journal of Clinical Nutrition 2011; doi: 10.3945/ajcn.111.017384
National Institutes of Health/Office of Dietary Supplements
Picture credit: Wikimedia Commons