The Nutrition Examination Research Digest (NERD) aims to provide rigorous, unbiased analysis of the latest and most important nutrition and supplementation studies. Click here to subscribe or login if already a subscriber .
Study under review: Curcumin for depression: a meta-analysis
Introduction
Depression is a condition that affects nearly 322 million people around the world and is one of the largest contributors to global disability. The World Health Organization estimates that the number of people living with depression increased by nearly 20% from 2005 to 2015.
A mainstay of treatment for this disabling condition is prescribing antidepressants that primarily work on the serotonergic system of the brain, although some researchers have proposed that they work through several other mechanisms, such as modulating neuroinflammation[1], the hypothalamic-pituitary-adrenal (HPA) axis[2], and circadian rhythm abnormalities[3].
Unfortunately, these drugs don’t work for everyone, and have been incredibly controversial. In 2018, the largest meta-analysis of antidepressants[4] to date combined 522 controlled trials and found that antidepressants had a small reduction on symptoms of depression and also increased adverse events. Some authors have disputed these results[5] and suggested that the effects are much smaller, and the risk of adverse events is substantially higher.
Another primary treatment used for depression is cognitive behavioral therapy, and while this has shown to be helpful in many trials[6], there is still much uncertainty about the treatment effects, and it can also be inaccessible[7] to many individuals suffering from depression due to costs and lack of information.
Thus, alternative and adjunct treatments have been investigated by several researchers. One of these alternatives is curcumin, a yellow compound found in the spice turmeric. It has anti-inflammatory[8], neuroprotective[9], antioxidant, and HPA-modulating effects[9], which have led researchers to explore whether it is effective for reducing symptoms of depression. Previous research[10] on it has shown promise.
NERD #30 covered a randomized controlled trial[11] that showed that curcumin supplementation also reduced symptoms of depression compared to participants who took a placebo. Since then, several other randomized controlled trials have investigated the impact of curcumin on depression.
The meta-analysis under review aimed to synthesize all this research and determine whether curcumin supplementation is more effective than placebo at reducing symptoms of depression.
Depression is a debilitating disorder that affects a notable part of the general population. Recent investigations indicate that the prevalence of it may be increasing. One main treatment is antidepressant drugs. However, the efficacy of these drugs has been disputed and they are well known for their association with adverse events. Other primary treatments, such as cognitive behavioral therapy, are often inaccessible to many individuals. Researchers have explored alternative treatments such as curcumin, which has shown promise in previous studies. This study sought to synthesize and combine the results from previous studies in order to investigate whether curcumin was an effective treatment for depression.
Who and what was studied?
What were the findings?
What does the study really tell us?
The big picture
Frequently asked questions
What should I know?
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NERD Mini: Higher vitamin E levels may increase the risk of coronary artery disease and heart attacks
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Isoflavones could boost cognition in theory by both slowing diseases that impact cognition and by impacting certain areas of the brain rich in estrogen receptors. But how much of an impact do they actually make?
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