Vitamin D is an essential nutrient that plays a role in bone health, immune function, and cell growth. Although some research has shown a link between low vitamin D and depression, there is no evidence that low levels cause depression.
People often associate vitamin D with sunshine, but it is available through food sources, too. Some people who find it difficult to consume enough of the vitamin choose to take supplements.
There is no proof that low levels cause depression or other mental health conditions, but experts do know that many people with depression have low vitamin D. This may be due to lifestyle factors such as inadequate nutrition and a lack of time outdoors.
Certain factors can increase the risk of having low vitamin D. These include having dark skin, being pregnant, having obesity, and living with a health condition such as gout or multiple sclerosis (MS).
This article looks at the link between vitamin D and depression. It also discusses the symptoms and treatment of vitamin D deficiency and depression.
Other researchers have investigated the link with the aim of identifying causation. For a
At the end of the study, they found no conclusive link between vitamin D and depression symptoms. They concluded that vitamin D3 supplementation did not play a role in preventing depression.
Despite being unable to prove causation, experts agree that vitamin D and depression are connected. This likely comes down to a complex combination of lifestyle factors and co-occurring conditions.
For example, people with depression may have difficulty eating a nutritious, well-balanced diet, so they may not be consuming enough dietary vitamin D. They may also be more likely to stay indoors, so their body is able to synthesize less vitamin D from sunlight.
Vitamin D is an essential fat-soluble vitamin. This means that the body absorbs it with fats and oils, storing it in fatty tissue.
One of its
Additionally, it helps prevent hypocalcemic tetany. This involuntary contraction of the muscles can cause muscle cramps and spasms.
Other roles of vitamin D in the body include:
- reducing inflammation in the body
- promoting proper immune function
- aiding in cell growth
- regulating glucose metabolism, which is the process of the body breaking down carbohydrates for energy
The amount of vitamin D that a person needs varies depending on their life stage. People who have an increased risk of brittle bones, including older adults, need more vitamin D.
According to the
Certain factors can increase a person’s risk of having low vitamin D levels.
Having a limited diet and not eating a variety of foods can increase a person’s risk of low vitamin D. As many animal products contain or are fortified with vitamin D, following a plant-based diet may also raise a person’s risk.
Limited sun exposure
People who do not get adequate unprotected sun exposure may not synthesize enough vitamin D. Those who live in regions with limited sunlight, such as in areas very far from the equator, are at particularly high risk.
Melanin inhibits vitamin D absorption, so people with dark skin will absorb less vitamin D than those with light skin.
A 2019 study used UV radiation to investigate vitamin D synthesis in people with different skin tones. It found that although melanin only inhibited a small amount of vitamin D3 production, this inhibition was enough to explain the differences across skin tones. The study authors advise people with dark skin to increase their UV exposure.
Some health conditions
Research has found a connection between vitamin D and depression in pregnant people and those with certain health conditions.
- Pregnancy: A
2020 reviewof 14 studies found that some research suggested a link between vitamin D deficiency and postpartum depression (PPD). However, other research has not confirmed this. The authors note that poor sleep quality played a significant role.
- Gout: A small
2019 studyshowed that low vitamin D was independently associated with depression in adults with gout.
- Stroke: According to a
2015 studyinvolving people who had had a stroke, those who developed depression afterward had significantly lower vitamin D levels than those who did not.
- MS: A
2021 studyfound a correlation between low vitamin D and depression in people with MS. The authors note that this association was more prevalent in males.
Treatment options are available to address a vitamin D deficiency and lessen depressive symptoms.
Vitamin D deficiency
People with a vitamin D deficiency
- Dietary supplements: People can take supplements containing vitamin D2, vitamin D3, or both.
- Nutrition: Foods containing vitamin D include fatty fish, egg yolks, and some cheeses. Other foods, such as milk and cereal, are frequently fortified with vitamin D.
- Sun exposure: Experts suggest that people get 5–30 minutes of unprotected sun exposure, ideally between the hours of 10 a.m. and 4 p.m.
- Vitamin D lamps: Special UV lamps can recreate the effects of sunlight, and people often use them to treat seasonal affective disorder.
The treatment for depression usually involves a combination of therapy and medication.
Depression is a complicated condition, and people react differently to treatment methods. Most doctors will recommend an antidepressant, such as a selective serotonin reuptake inhibitor (SSRI), alongside talk therapy.
Learn more about the treatment options for depression.
Studies have shown a connection between low vitamin D levels and depression, but experts do not fully understand why this link exists. Some theories suggest that people with depression have lifestyle practices that make them more likely to have low levels of vitamin D.
People can treat low vitamin D levels with supplements, dietary changes, and increased sun exposure.