Medically reviewed by Kristin Hall, FNP
Written by Our Editorial Team
Last updated 9/17/2021
The role of vitamin D in depression is far from clear. Many articles will tell you that your vitamin D level and any vitamin D deficiency you may have could be directly contributing to your risk of depression.
Whether your proposed source of vitamin D is sunlight, or you’re going to get your dose of vitamin D from increased dietary intake, there’s more to this than doing the vitamin equivalent of chugging water after a long, dehydrated day.
Intake of vitamin D is a crucial element of health for the function of plenty of organs and bodily processes, but the link to this essential vitamin and mental disorders is less clear—and the risk for depression due to vitamin D insufficiency is less direct than you might believe.
We’ll walk you through what the medical community knows — and what they believe — but first, so this will all make sense later, let’s cover some depression basics.
According to the National Institute of Mental Health depression is defined as a mood disorder, which is identified by recurring moods and thoughts of down, sad or low feeling.
It’s important to understand that a diagnosis requires a pattern. To be diagnosed with depression, you have to feel these emotions nearly every day for at least two weeks, and for as long as years.
Different types of depression, like seasonal affective disorder (SAD), have more specific requirements, but the NIMH explains that the two most common forms of depression are major depression (MD) and persistent depressive disorder (PDD).
Major depression is typically characterized by periods of more extreme lowness, for approximately two weeks.
Persistent depressive disorder typically goes on for at least two years, and during this time the severity will vary.
A variety of factors are thought to be possible causes and risk factors for depression—genetic, environmental, biological and psychological causes have all been linked in some way.
In men, symptoms of depression include feeling tired, irritable and angry, and if you have depression, you may have sleep issues and motivation problems, you might behave recklessly and you face an increased risk of abusing drugs and alcohol.
You may also lose interest in the things you once enjoyed, experience weight fluctuations, occasional suicidal thoughts, frequent fatigue and occasional feelings of hopelessness, as well as physiological symptoms that manifest as headaches, cramps and even stomach and digestive problems.
Vitamin D deficiency is more than a bit player in the pro-milk ads of the 2000s — so much more, really. And in addition to milk, we get it from other foods, supplements and sun exposure.
The right vitamin D level is good for you because it promotes calcium absorption, which among other things, is good for your bone density as you age. It’s also necessary to prevent muscle cramps and spasms, and to avoid osteoporosis and other bone diseases.
Outside of the bones and muscles, the effects of vitamin D can reduce inflammation and aid in neuromuscular and immune function.
As for your brain? Levels of vitamin D are crucial there, as well.
It’s necessary for certain brain functions, and there are neuron receptors for it that are thought to be involved in depression mitigation — though that science is admittedly thin.
One study found that vitamin D status may play a role in moderating inflammatory cytokines, epinephrine production, norepinephrine production, and the regulation of dopamine and serotonin, all of which are crucial elements of mood regulation.
But the relationship between serum vitamin levels isn’t fully understood, and we don’t know for certain that depression can be caused by low vitamin D levels.
What we know about the relationship of vitamin D to depression isn’t much.
For instance, we know that vitamin D supplementation is not a cure for depressed people.
Clinical trials of dietary supplement treatment reported by the NIH did not find any statistically significant benefits or impact on depressed individuals from vitamin D supplementation.
But that’s not the complete picture. A systematic review of 14 observational studies, accounting for a total of more than 30,000 adults, did find an association between vitamin D deficiency and depression.
That’s a statistically significant number of people… without a statistically significant explanation.
What we’re left with are more questions. For instance, is it possible that the correlation between low vitamin D levels and depression is the result of inadequate sunlight? Possibly.
The explanation for that would be found in conditions like seasonal affective disorder, which can be treated with light therapy. This would suggest, however, that sunlight is a more significant element of depression than the vitamin D itself.
Likewise, it’s possible that low levels of vitamin D are a symptom of depression, but increasing serum levels of vitamin D is not a cure, and fails to yield results.
Still, other studies suggest the link should be investigated further.
One, from 2011, found overlap in that the groups most at risk for depression (elderly, adolescents, obese individuals and those with chronic illness) are also frequently those at risk for vitamin D deficiency, and that exercising outdoors and eating more vitamin D-rich foods could be a simple and cost effective solution for individuals at risk of depression.
So aside from trying to make up for your vitamin D deficiency with an overdose of a vitamin D supplement (don’t do that), how would you actually treat depression?
Well, there are a number of ways that the medical community would recommend you do that — including medication, therapy and lifestyle changes.
The best approach may be a combination of two or more, under the guidance of a healthcare professional. Let’s take a brief look at these:
Antidepressants are designed to affect the serotonin serum levels in your brain. When taken under the supervision of a trained mental health professional, they can be effective at regulating mood and helping you deal with depression.
The most common of these are selective serotonin reuptake inhibitors (SSRIs), as they’ve been found to cause fewer side effects, which are mostly limited to sexual dysfunction, insomnia, sleep disturbances, weight changes, anxiety, bouts of dizziness, dry mouth, headache, and a few others.
The FDA has previously issued a blackbox warning for the use of SSRIs and other antidepressant medications for increased risk of suicidality among patients ages 25 and younger.
Psychotherapy is always a recommended option, especially alongside medication.
One of the most popular forms of psychotherapy is Cognitive Behavioral Therapy (CBT, which is a system designed to help patients learn to observe and rethink unhealthy patterns of thought.
This is best done with the help of a mental health professional, and if you feel like you could use help contextualizing negative thoughts, this might be the right treatment for you.
It doesn’t just have to be about your vitamin D level or being worried about a vitamin D deficiency.
A healthcare professional may advise you to address health concerns related to weight, blood pressure, dietary habits and other issues that could be having negative effects on your health — mental or otherwise.
Exercise, for example, has been found to be as effective as drugs in certain conditions.
As the bearer of bad news, it’s our job to tell you that your depressive symptoms aren’t going away just because you address your vitamin D deficiency.
Vitamin D supplementation might be a necessary health status improvement for you and your body, but it’s by no means a stand-in for proper treatment for depression in adults or children.
Normal vitamin D levels aside, the effects of vitamin D on your risk of depression may have little or no meaning in your mental health, and vitamin D receptors may not affect your risk of depression or depressive symptoms.
Though a variety of treatments for depression are available, you’re not the best person to pick a treatment for yourself. That’s the job of a mental health professional.
And your trust in the relationship between vitamin D deficiency and clinical depression is simply not as important to your health as a professional’s.
We get that loading up on vitamin D pills might be an easier action to take than opening up to a professional, but it’s not going to solve the problem. If anything, it might make things worse.
Talk to someone, and consider contacting a mental health professional who can give you personalized advice and treatment you need, and tell you whether you have a vitamin D deficiency or not.