Food and Behaviour Research

Donate Log In

Do Nutrient Supplements Have Any Effect on Mental Disorders? World's largest review of the evidence

Traci Pedersen

supplements

A growing number of studies have examined the benefits of nutrient supplementation in people with mental disorders. But which supplements have been proven to work - and for which disorders?

FAB RESEARCH COMMENT:

In this new, open-access review, leading international experts provide a comprehensive analysis of the best evidence to date on whether supplementation with specific nutrients can help in the management of mental health disorders, by examining systematic reviews and meta-analyses of clinical trials investigating specific nutrients for specific psychiatric conditions.

Results show that some nutritional treatments ARE now clearly 'evidence-based'.  The news article below summarises the main findings - but FAB followers will already be familiar with the areas where current clinical trial evidence is strongest, namely: 
  • long-chain omega-3 fatty acids* for major depression and other mood disorders, and 
  • long-chain omega-3 for ADHD (albeit with more modest benefits)
* For depression, it is omega-3 EPA (rather than DHA) that clinical trials have shown most effective. And importantly, this is in addition to any standard treatment). For detaled clinical treatment guidelines, see:

Very importantly, the review also found no evidence of harm from nutritional supplementation.

This comprensive review is obviously helpful in showing the importance of nutrition as an additional treatment option for psychiatric disorders. 

However, the focus on 'which nutrient, for which condition' - doesn't take into account 
the variability within any group of patients with the same psychiatric diagnosis (most of whom also have co-ccurring conditions that may well be relevant) - or the fact that nutrients work in synergy - not in isolation.  So these findings inevitably underestimate the potential benefits of nutritional and dietary treatments when these can be individually tailored.

In practice, clinicians always need to consider the patient's individual symptom profile, diet and nutritional status, and general health - and ideally, help patients to improve their overall diet and lifestyle - using supplements only as needed to fill any remaining 'nutrient gaps'.

For details of this research, and additional FAB comments (with links to other relevant articles), please see:


See also the related news article:


From PsychCentral, 20/10/2019

A growing number of studies have examined the benefits of nutrient supplementation in people with mental disorders. But which supplements have been proven to work - and for which disorders?

Now, in the world’s largest review of this topic, an international team of scientists led by Australia’s National Institute of Complementary Medicine (NICM) examined the  best available evidence and narrowed it down to which specific nutrients can assist in the management of certain mental health disorders.

The findings are published online in the journal World Psychiatry.

The team examined 33 meta-analyses of randomized control trials and data from 10,951 people with mental health disorders including depression, stress and anxiety disorders, bipolar disorder, personality disorders, schizophrenia and attention-deficit/hyperactivity disorder (ADHD).

The aim was to provide a clear overview of the benefits of specific nutrient supplements - including dosage, target symptoms, safety and tolerability - across different mental disorders.

Although the majority of nutritional supplements assessed did not significantly improve mental health, the researchers found strong evidence that certain supplements are an effective additional treatment for some mental disorders, supportive of conventional treatment.

All nutrient supplements were found to be safe when recommended dosages and prescriptive instructions were adhered to and there was no evidence of serious adverse effects or contraindications with psychiatric medications.

Among the results:

  • the strongest evidence was found for omega-3 supplements (a polyunsaturated fatty acid) as an add-on treatment for major depression. Omega-3 reduced symptoms of depression beyond the effects of antidepressants alone;

  • there was some evidence to suggest that omega-3 supplements may also have small benefits for ADHD;

  • there was emerging evidence for the amino acid N-acetylcysteine as a useful adjunctive treatment in mood disorders and schizophrenia;

  • special types of folate supplements may be effective as add-on treatments for major depression and schizophrenia, however folic acid was ineffective;

  • there was no strong evidence for omega-3 for schizophrenia or other mental health conditions;

  • there is currently a lack of compelling scientific evidence supporting the use of vitamins (such as E, C, or D) and minerals (zinc and magnesium) for any mental disorder.

According to the researchers, the findings can be used to produce more evidence-based guidance on the usage of nutrient-based treatments for various mental health conditions.

“While there has been a longstanding interest in the use of nutrient supplements in the treatment of mental illness, the topic is often quite polarizing, and surrounded by either over-hyped claims or undue cynicism,” said lead author Dr. Joseph Firth, Senior Research Fellow at NICM Health Research Institute, Western Sydney University and Honorary Research Fellow at The University of Manchester.

“In this most recent research, we have brought together the data from dozens and dozens of clinical trials conducted all over the world, in over 10,000 individuals treated for mental illness.”

“This mass of data has allowed us to investigate the benefits and safety of various different nutrients for mental health conditions, on a larger scale than what has ever been possible before.”

Senior author Professor Jerome Sarris of the NICM institute said as the role of nutrition in mental health is becoming increasingly acknowledged, it was vital that an evidence-based approach be adopted.

Future research should aim to determine which individuals might benefit most from evidence-based supplements and to better understand the underlying mechanisms so we can adopt a targeted approach to supplement use in mental health treatment,” said Sarris.

“The role of the gut microbiome in mental health is a rapidly emerging field of research, however more research is needed into the role of ‘psychobiotics’ in mental health treatment.”