Low Vitamin D Common; May Affect Depression

beautiful girl enjoying the summer sun

Vitamin D has been the target of a wide variety of studies lately looking at everything from how it affects your blood pressure to the length of your life. For several years, vitamin D levels have been linked to depression, but most of these studies were done in older adults who were often in poor health. A new study out this week has looked to fill that gap by examining whether vitamin D levels play a role in depression for younger women as well.

How is vitamin D related to depression?

Vitamin D was first linked to depression in a variety of population studies that looked at the blood of older women and compared it to their risk of a variety of diseases. Among the things that jumped out was vitamin D, which seemed in some studies to be associated with the risk of being depressed. But the data hasn’t been conclusive. Studies that have examined all of the available data have found relationships in both directions, with some showing no effect of vitamin D levels on depression.

In spite of that, there are some thoughts on how vitamin D might relate to mood. Vitamin D has receptors in areas of the brain involved in emotion and also helps produce some of the chemicals in the brain responsible for mood. It’s also involved with activation of the immune system, which could in some cases trigger a stress response and affect a person’s emotions.

Why was it important to do this study in young women?

More studies needed to be done to conclusively say whether or not vitamin D was related to mood disorders. But on top of that, it was unclear if the studies that existed related to the entire population or just those tested directly in the research. If vitamin D affected mood early in life, it might be possible to intervene when someone’s vitamin D levels were first dropping to avoid a more serious case of depression later in life. If there was no effect, health care providers could focus on vitamin D levels in older groups without worrying about younger women. This study helped both add to the literature on depression and vitamin D while also expanding the ages tested.

How did the researchers test this association and what did they find?

The researchers recruited 185 young, healthy college women and surveyed them weekly to assess any symptoms of depression they might have. They also drew blood at the beginning of the study and then at the end of the study five weeks later. They recruited students from all times of the year so they could be sure that season wasn’t playing a role and also asked about a variety of factors that could relate to vitamin D levels, like the amount of exercise they get or the amount of time they spent outside.

The researchers found that lower levels of vitamin D predicted higher levels of depressive symptoms during the five weeks of the study. While the relationship was just an association, the researchers point out that the opposite wasn’t true, namely that more depressive symptoms didn’t predict lower vitamin D levels.

Additionally, the researchers found that the women were surprisingly low in vitamin D. About six in 10 women of color were below healthy levels of vitamin D and about a third of all other women were low.

How does this affect me?

The study provides support for the idea that vitamin D and mood are related in some way and that low levels may be linked to depression. Even if you’re a young, healthy woman, you may still have low vitamin D levels, which can impact your health in other important ways. The test is easy to get, and supplementation is simple and straightforward if your levels happen to be below where they should be.