- Lindsey Dalton
- December 8, 2023
Can Vitamin D Supplementation Help Depressive Symptoms?
Depression is a common mental disorder that over 280 million people live with worldwide.1 There are a variety of reasons that someone could develop depression, and some of those reasons include imbalances within the body. There are multiple ways to manage depression including medications, therapy/counseling, exercise, and vitamin supplementation. One factor that has been linked to depression is a low circulating vitamin D [25-hydroxyvitamin D3] level. Vitamin D supplementation is of great importance for everyone as it is a vitamin that is needed for building and maintaining healthy bones. The Cleveland Clinic estimates about 35% of American adults have vitamin D deficiency.2 This leads to two questions that we need to answer. First, can there be a change in depressive symptoms while supplementing vitamin D? Second, how much vitamin D should be supplemented to improve these symptoms?
A systematic review and meta-analysis reviewed 41 articles and found evidence that demonstrated positive effects in individuals with major depressive disorder (MDD) and those with moderate, but clinically relevant depressive symptoms. Multiple subgroup analyses were completed to assess the impact of supplementation for those with a variety of characteristics. Firstly, there was an effect observed in those with MDD compared to those who were otherwise healthy. In those with diagnosed MDD (n = 1,166) there was a sizeable effect compared to placebo (Hedges’ g = −0.729, 95% CI −1.100 to −0.358, p < 0.001). In for those who were otherwise healthy, there was a small effect that favored placebo (Hedges’ g = 0.043, 95% CI 0.025 to 0.061, p < 0.001). This demonstrates a positive effect for those that live with MDD.3
In addition to MDD, the impact of baseline levels of vitamin D (25-hydroxyvitamin D3) was analyzed. There was a similar effect in both subsets that included levels ≤ 50 nmol/L and those > 50 nmol/L. There was a marginally larger effect observed at doses over 2,000 IU per day than at doses of 2,000 IU or less per day. Particularly, the effect seemed to be larger in the subgroup with the largest doses of over 4,000 IU per day compared to the subgroup with doses of 4,000 IU or less per day. An additional meta-analysis showed that a daily dose of 2,800 IU or more for at least 8 weeks was able to impact the incidence of depression for those with low levels of 25-hydroxyvitamin D3 (SMD: −0.33; 95%CI: (−0.60, −0.07); p = 0.01).4
It is clear to see that there appears to be an effect, but did any of the articles in this meta-analysis/systematic review consider those that were taking antidepressant medications? There was another subgroup analysis for 14 trials that considered those who were able to take antidepressants outside of the protocol. This demonstrated a small, yet statistically significant effect favoring vitamin D supplementation (Hedge’s g = -0.162, 95% CI -0.286 to -0.039), p = 0.01). In addition to this, 17 studies that excluded the use of antidepressants outside of the trial protocol showed a moderate-sized effect (Hedges’ g = −0.461, 95% CI −0.673 to −0.250, p < 0.001). 3
Ultimately, could regular vitamin D supplementation aid in alleviating depressive symptoms? This research demonstrates varying levels of effect across populations with a variety of characteristics. In addition to known effective methods of treatment including therapy and medications, adding in doses of at least 2,800 IU per day can make an impact within 8 weeks time. As previously mentioned, many adults are deficient in vitamin D, so adding in a supplement to help with this deficiency could lead to multiple positive downstream effects including the alleviation of depressive symptoms and maintaining bone health. Work with a provider to check your level and determine the most appropriate dose for you!
Written by Katelynn Webster, PharmD Candidate
Edited by Lindsey Dalton, PharmD
References
- World Health Organization. Depressive disorder (depression). World Health Organization; 2023. Accessed November 14, 2023. https://www.who.int/news-room/fact-sheets/detail/depression#:~:text=Approximately%20280%20million%20people%20in,among%20women%20than%20among%20men
- Vitamin D deficiency. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/15050-vitamin-d-vitamin-d-deficiency. Last reviewed August 2, 2022. Accessed November 27, 2023.
- Mikola T, Marx W, Lane MM, et al. The effect of vitamin D supplementation on depressive symptoms in adults: A systematic review and meta-analysis of randomized controlled trials [published online ahead of print, 2022 Jul 11]. Crit Rev Food Sci Nutr. 2022;1-18. doi:10.1080/10408398.2022.2096560
- Xie F, Huang T, Lou D, et al. Effect of vitamin D supplementation on the incidence and prognosis of depression: An updated meta-analysis based on randomized controlled trials. Front Public Health. 2022;10:903547. Published 2022 Aug 1. doi:10.3389/fpubh.2022.903547
Dr. Dalton’s areas of focus include disease state management, medication therapy management, and health/wellness coaching. She is a Whole30 Certified Coach, and is passionate about helping people improve their lives through lifestyle modifications. She has seen first hand how changing food alone can vastly improve your health.
