There is an increasing interest in herbal remedies and nutritional supplements as an alternative to conventional medicines.Depression, anxiety and insomnia are among the most common reasons for people to use complementary medicines (Thomas at al 2004). In the UK, estimates of the proportion of the general population using these range from 14% to 30% .
Is there enough evidence to support the use of nutritional supplements and herbal remedies in depression? Dhingra and Parle review the evidence in this overview article.
Data Search period was 98-2011. Studies with out formal diagnosis using standard criteria, those with no reliable measurement of symptoms and those with severe depression were excluded.
St John’s Wort: Cochrane review showed that it has a modest effect over placebo in the treatment of mild to moderate depression in a similar range as standard antidepressants.The evidence base in severe major depression is insufficient to draw conclusions. Bio active content can vary widely between available preparations.It will reduce plasma levels of anticoagulants, oral contraceptives, and antiviral agents. With SSRI, it can lead to serotonin syndrome.Health professionals are advised not to prescribe St Johns Wort due to lack of dose standardisation.
Folate: People with folate deficiency are more likely to suffer from depression ad have more lasting relapse and are less likely to respond to antidepressant drugs . 3 small RCTS were identified.There is insufficient evidence to recommend folate for the treatment of depression. Authors recommend screening and treating depressed patients for folate deficiency.Folate supplementation at doses greater than 1 mg/d has been associated with increased risk of colorectal cancer.
Polyunsaturated Fatty Acids (PUFAs): Neurons contain high levels of omega-3 fatty acids, where they influence phospholipid membrane fluidity. In a recent meta analysis of 16 RCTs that enrolled only patients diagnosed with major depressive disorder (MDD), the pooled standardized mean difference (SMD) was 0.41 (95% CI 0.26 to 0.55), which represents a 3- to 4-point change in Ham-D scores(Appleton et al. Am J Clin Nutr 2006;84(6):1308-16.). PUFA’s role is promising. Red blood cell omega-3 levels could be useful in depression.
S-Adenosyl-L-Methionine (SAMe): SAM-e is involved in the methylation cycle where it acts as a methyl donor to membrane phospholipids, myelin, choline, catecholamines, and other molecules important for brain function.A recent systematic review reported benefit in 7 of 7 trials using parenteral SAM-e and in 4 of 5 studies using oral SAM-e at doses of 1600 mg/d .There is some evidence to support the use of SAM-e, but this requires confirmation by larger studies
Inositol: Inositol is an isomer of glucose. Four trials were identified, with a total of 141 participants. These were short term trials of double-blind design. The trials did not show clear evidence of a therapeutic benefit or any evidence of poor acceptability.
Ginkgo biloba: A traditional Chinese medicine. No good quality evidence was identified for the use of Ginkgo biloba in depression.
Selenium: No good quality evidence was identified
Ginseng: This is popular herbal remedy.No good quality evidence was identified
Glutamine is a naturally occurring, non-essential amino acid. No good quality evidence was identified.
Chromium: No good quality evidence was identified
Conclusion:Except for St Johns wort, no clear evidence exists for use in depression.Limited evidence support use of PUFA and SAMe.
This is on overview of the topic. It is possible that all herbal remedies may not be covered in this. See another review on this topic: Herbal medicine for depression, anxiety and insomnia: a review of psychopharmacology and clinical evidence. Sarris J, Panossian A, Schweitzer I, Stough C, Scholey A.Eur Neuropsychopharmacol. 2011 Dec;21(12):841-60.
Summary of the article: Herbal remedies and nutritional supplements in the treatment of depression.A review. Sammer Dhingra, Milind Parle, Bulletin of psychopharmacology, Vol 22,N 3;2012