Low Vitamin D Linked to Depression in Young Women

Vitamin D insufficiency may raise the odds of depressive symptoms in college-aged women.

Discussing the study’s findings, which were published in Psychiatry Research, lead author David Kerr, PhD, associate professor in the School of Psychological Science at Oregon State University, told Pharmacy Times that patients who consume vitamin D-fortified foods may be surprised to learn that they are still at risk for vitamin D insufficiency.

“This is because the amount of vitamin D in a typical diet is often too low to make up for a lack of sun exposure,” Dr. Kerr said, noting that pharmacists may be able to educate patients about this fact.

Dr. Kerr’s study measured depressive symptoms and vitamin D levels among 185 healthy female students residing in the Pacific Northwest. The undergraduate students completed the Center for Epidemiologic Studies Depression survey in the fall, winter, and spring semesters for a total of 4 weeks. The researchers also took blood samples to study the students’ serum levels of vitamin D₂ and C, the latter of which served as a control variable.

Their results showed that 42% of women had vitamin D insufficiencies in the first week of the study, and 46% had them in the last week. Rates of depressive symptoms were between 34% and 42% over the study period. After controlling for season, body mass index, race, diet, exercise, and time outside, lower vitamin D levels predicted clinically significant depressive symptoms, according to the researchers.

As spring turned to fall, students had higher levels of vitamin D and lower levels of depressive symptoms, which led the researchers to believe that differences in depression by season could be partially explained by seasonal changes in vitamin D.

Dr. Kerr told Pharmacy Times that low vitamin D levels have also been associated with impaired immune function, some forms of cancer, and cardiovascular disease.

However, he guessed that not all young adults may want to make dietary or lifestyle changes or spend money on supplements.

“Young adults may be more motivated to make such changes if they see a more immediate benefit of increasing their intake of vitamin D,” Dr. Kerr told Pharmacy Times. “If our findings on depression are supported in additional research, then pharmacists could use this information to persuade young people.”