DALLAS—Individuals who have low levels of vitamin D have an increased risk of depression, according to a new study published in Mayo Clinic Proceedings. The findings may be significant for major depressive disorder that affects nearly 1 in 10 U.S. adults.
Researchers at UT Southwestern Medical Center examined results of almost 12,600 participants from late 2006 to late 2010 who participated in the Cooper Center Longitudinal Study. They found higher vitamin D levels were associated with a significantly decreased risk of current depression, particularly among people with a prior history of depression. Low vitamin D levels were associated with depressive symptoms, particularly those with a history of depression, so primary care patients with a history of depression may be an important target for assessing vitamin D levels. The study did not address whether increasing vitamin D levels reduced depressive symptoms.
While the findings did not determine whether low vitamin D contributes to symptoms of depression, whether depression itself contributes to lower vitamin D levels, or chemically how that happens, the researchers speculate vitamin D may affect neurotransmitters, inflammatory markers and other factors, which could help explain the relationship with depression.
