Study leads the way for vitamin D testing in depressed patients
By Jessica Brown
A new study has revealed that vitamin D intake affects depression. This vitamin has long been linked to mood, especially with Seasonal Affective Disorder (SAD), when a lack of sunshine-derived vitamin D has been believed to contribute to depression.
There have been several studies before this, looking at the link between depression and vitamin D, but this one looks particularly at the direct effect of vitamin D on depressed patients in a controlled study.
The study was presented at The Endocrine Society’s 94th Annual Meeting in Houston, Texas, on June 23rd, 2012. It included three female participants who were initially deficient in vitamin D, aged between 42 and 66, had moderate to severe depression and were taking antidepressants. They received oral vitamin D replacement therapy for eight to 12 weeks and after this time, their vitamin D levels rose to normal levels and they all recorded significant improvements in their depression.
The women had no change to their environment or medication during the study, which gives a strong case to the increase in vitamin D being the influencing factor. The participants were also being treated for either Type 2 diabetes or an underactive thyroid.
One of the women’s depression went from severe to mild, according to the Beck Depression Inventory – a questionnaire that measures levels of depression. Another woman’s score fell to ‘minimal symptoms of depression’ and the third participant’s score fell into the ‘mild’ range.
There are several other studies that have suggested that vitamin D can affect mood and depression, but Dr Pathak, an endocrinologist at Bayhealth Medical Center in Dover, America, says that there is a need for large, good-quality, controlled clinical trials to prove whether there is a real relationship. "If this association is confirmed, it may improve how we treat depression", she says.
This research alone cannot conclude that a deficiency in vitamin D can have an impact on depression, but along with the growing number of other studies, it does provide evidence of a link between the two.
Dr Pathak says that this study, along with further, more in-depth research, could prove that screening depressed patients who are at risk of a vitamin D deficiency is a cost-effective and easy therapy to treat patients with depression.
Vitamin D can be found in food such as milk, tuna, salmon, mackerel, egg yolks and cheese. It can, however, be difficult to get the recommended amount from our diet alone. Our bodies also produce vitamin D when exposed to sunlight. It is said that a ‘significant’ proportion of the UK population have low levels of the vitamin.