By Elizabeth Foley
Let’s talk about depression. According to studies, one in six people will experience depression at some time in their life (1). Depression is marked by loss of interest in activities you once enjoyed and persistent feelings of sadness. When someone is depressed, their emotional and physical problems increase their challenges to function at home and work. On average, depression first appears in a person's teenage years to their mid-20s. However, depression can occur at any time.
According to a number of studies, there is a link between vitamin D deficiency and depression. Still, further research is needed to fully understand how the two are connected.
Here are five questions we’ve asked to better understand how vitamin D deficiency affects depression:
It is statistically shown that people with low vitamin D levels are at a greater risk of experiencing depression. This information may make you wonder—does that lack of vitamin D actually make you depressed? One study found that participants with depression also had low vitamin D levels (2). Of course, the causes and symptoms of depression are complex. So, researchers note that vitamin D deficiency alone cannot be identified as the cause or cure of depression. However, further studies are being conducted to explore the reasons increased numbers of people who are experiencing vitamin D deficiency are also experiencing depression. Studies are also investigating the reasons that taking a vitamin D supplement decreased feelings of depression in those with vitamin D deficiencies.
Can taking vitamin D improve your mood and make you feel happy? It turns out that vitamin D receptors are located in the same areas of the brain that are associated with depression. This leads researchers to believe that vitamin D is important not only for healthy brain function, but also mood stabilization. The research points to insufficient levels of vitamin D playing a role in depression and other mental illnesses (3). In this study, researchers found that people with depression who also took vitamin D supplements noticed a decrease in their symptoms. So, for those with a vitamin D deficiency, taking a supplement did improve mood and feelings of happiness. It is important to note that this improvement in mood was only found in people who were depressed or struggling with mental illness. While this research shows that vitamin D might play an important role in regulating mood and warding off depression, further studies are needed to determine if vitamin D can improve feelings of wellbeing in people who are not experiencing mental health issues.
It would be fantastic if childhood depression could be curbed with vitamin D supplements. Scientists are considering the connection between children who are struggling with depression and vitamin D deficiency. They learned that children experience depression for a number of reasons: they may become depressed as a side effect of medications or in conjunction with psychiatric disorders. Research shows that children may need vitamin D even more than adults do, especially if they are taking medications (4). When children are facing mental health concerns, addressing vitamin D deficiency is one step towards reducing symptoms. One study found that vitamin D deficiency is more common in children with more severe psychiatric disorders confirming that children who struggle with psychotic symptoms had extremely low vitamin D levels (5),.According to another study, children who are on the Autism spectrum and children with bipolar disorder have higher rates of severe vitamin D deficiencies (6). All of these studies point to the need to address vitamin D deficiencies as a way of reducing the risk for depression in children with mental health concerns.
We know the CDC recommends breastfeeding mothers take a vitamin D supplement. Could vitamin D also help with postpartum depression? Postpartum depression is a depressive state that can occur after giving birth. Most new moms who experience postpartum depression report mood swings, crying spells, anxiety and difficulty sleeping. One study found a 20% reduction in the risk of developing postpartum depression for women with higher levels of vitamin D after giving birth (7). Researchers believe this may be attributed to the fact that vitamin D behaves like a hormone (8). As a result, vitamin D protects the brain, lowers inflammation and has the ability to boost your mood. Thus, it is reasonable to say vitamin D does have the potential to help mothers who are experiencing postpartum depression.
Of course, the million-dollar question is, can vitamin D actually cure depression all together? In a study where researchers examined the usefulness of vitamin D as an antidepressant, no significant reduction in depression was found in trials where a vitamin D supplement was used to treat depression (9). However, in this study, participants did not suffer from a vitamin D deficiency prior to trials. This leaves room for further investigation on individuals who were experiencing both depression and vitamin D deficiency at the same time.
The bottom line is, no large-scale study has found that vitamin D “cures'' depression. Further studies are needed to determine whether vitamin D can be used to resolve depressive symptoms. We do know that those with vitamin D deficiency can benefit from a supplement to counteract the effects of depression. Still, there is not enough research to prove vitamin D deficiency actually causes depression and it is undetermined if low levels of vitamin D worsen depression. However, some research indicates that people with depression have lower levels of vitamin D than their counterparts without depression.
If you are dealing with depression, talk to your doctor about your vitamin D levels and see if a supplement might be helpful. In time, we will have a better understanding of the link between vitamin D deficiency and depression. For now, we can only state that a link exists, and some people with depressive symptoms benefit from addressing their vitamin D levels.