Sunlight, Vitamin D, and Depression
This is the Medscape Psychiatry Minute. I am Dr. Peter Yellowlees.
Vitamin D metabolism is dependent on sunlight, and lack of sunlight is linked to depression, so it is logical to assume that a lack of vitamin D might be a cause of depression. But is it? A team of investigatorsfrom Tromsø in Norway have performed a study to compare depressive symptoms in participants with low and high serum vitamin D levels and to examine whether supplementation with vitamin D would improve symptoms in those with low serum levels.
A sample of 230 participants with low vitamin D levels was randomly assigned to receive either placebo or 40,000 IU vitamin D per week for 6 months, and 114 individuals with high serum levels were used as nested controls. Depressive symptoms were evaluated with several well-validated depression rating scales.
The investigators found that the participants with low levels of vitamin D were more depressed than participants with high levels, but in the intervention study, no significant effect of high-dose vitamin D was found on depressive symptom scores when compared with placebo. From a clinician's perspective, our advice to our depressed patients must remain the same: Stick to the sunlight rather than taking extra vitamin D.
This article is selected from Medscape Best Evidence. I'm Dr. Peter Yellowlees.
Abstract
This is the Medscape Psychiatry Minute. I am Dr. Peter Yellowlees.
Vitamin D metabolism is dependent on sunlight, and lack of sunlight is linked to depression, so it is logical to assume that a lack of vitamin D might be a cause of depression. But is it? A team of investigatorsfrom Tromsø in Norway have performed a study to compare depressive symptoms in participants with low and high serum vitamin D levels and to examine whether supplementation with vitamin D would improve symptoms in those with low serum levels.
A sample of 230 participants with low vitamin D levels was randomly assigned to receive either placebo or 40,000 IU vitamin D per week for 6 months, and 114 individuals with high serum levels were used as nested controls. Depressive symptoms were evaluated with several well-validated depression rating scales.
The investigators found that the participants with low levels of vitamin D were more depressed than participants with high levels, but in the intervention study, no significant effect of high-dose vitamin D was found on depressive symptom scores when compared with placebo. From a clinician's perspective, our advice to our depressed patients must remain the same: Stick to the sunlight rather than taking extra vitamin D.
This article is selected from Medscape Best Evidence. I'm Dr. Peter Yellowlees.
Abstract