No effect ofn-3 long-chain polyunsaturated fatty acid (EPA and DHA) supplementation on depressed mood and cognitive function: a randomised controlled trial

Abstract

Low dietary intakes of the n-3 long-chain PUFA (LCPUFA) EPA and DHA are thought to be associated with increased risk for a variety of adverse outcomes, including some psychiatric disorders. Evidence from observational and intervention studies for a role of n-3 LCPUFA in depression is mixed, with some support for a benefit of EPA and/or DHA in major depressive illness. The present study was a double-blind randomised controlled trial that evaluated the effects of EPA þ DHA supplementation (1·5 g/d) on mood and cognitive function in mild to moderately depressed individuals. Of 218 participants who entered the trial, 190 completed the planned 12 weeks intervention. Compliance, confirmed by plasma fatty acid concentrations, was good, but there was no evidence of a difference between supplemented and placebo groups in the primary outcomenamely, the depression subscale of the Depression Anxiety and Stress Scales at 12 weeks. Mean depression score was 8·4 for the EPA þ DHA group and 9·6 for the placebo group, with an adjusted difference of 21·0 (95 % CI 22·8, 0·8; P¼ 0·27). Other measures of mood, mental health and cognitive function, including Beck Depression Inventory score and attentional bias toward threat words, were similarly little affected by the intervention. In conclusion, substantially increasing EPA þ DHA intake for 3 months was found not to have beneficial or harmful effects on mood in mild to moderate depression. Adding the present result to a meta-analysis of previous relevant randomised controlled trial results confirmed an overall negligible benefit of n-3 LCPUFA supplementation for depressed mood.

Influences of protein to energy ratios in breakfast on mood, alertness and attention in the healthy undergraduate students

“…Their major theory was that a meal high in carbohydrate increased the rate that tryptophan entered the brain, leading to an increase in the level of the neurotransmitter serotonin that modulates mood. As for fat, it is thought that in many countries current population intakes of the n-3 long-chain PUFA (LCPUFA; also known as long chain omega-3 fatty acids) EPA and DHA are lower than optimal for a variety of health outcomes [2,4]. However, Peter J. Rogers' [5] studies that have shown substantially increasing EPA and DHA intake for 3 months was found not to have beneficial or harmful effects on mood in mild to moderate depression.…”

1. The anticonvulsant effects of docosahexaenoic acid in rodents

“…These studies, however, have produced confusing results. While a few studies have reported beneficial effects of n-3 PUFAs supplementation on depression (Nemets et al, 2002;Peet and Horrobin, 2002), other studies have reported no effect (Marangell et al, 2003;Rogers et al, 2008). A recent meta-analysis has concluded that perhaps only EPA, and not DHA, has beneficial effects on depression, which has led to the mixed results reported in clinical studies (Martins, 2009).…”

Nutrition and Behaviour: The Role of ω3 Fatty Acids

“…Poland). British researchers [56] conducted a large double-blind randomised controlled trial to evaluate the effects of EPA+DHA supplementation (1,5 g/d) on mood and cognitive function in mildly to moderately depressed individuals (190 participants completed 12 weeks intervention). Compliance, confirmed by plasma fatty acid concentrations, was good, but there was no evidence of a difference between supplemented and placebo groups in the depression subscale of DASS (Depression, Anxiety and Stress Scales) at 12 weeks (adjusted difference in mean: -1,0; 95% CI; P=0,27).…”