The first study evaluated 46 depressed women1, aged 66 – 95, in an Italian nursing home. It was an 8 week, randomized, double-blind, placebo-controlled trial. The women took 2500 mg of DHA/EPA per day (830 mg DHA and 1670 mg EPA). The study proved quite effective as the researchers reported that the fish oil fatty acids were “efficacious in the amelioration of depressive symptoms and quality of life in the treatment of depressed elderly female patients.”
A second study looked at major depression in 432 Canadians2. This study was also an 8 week, randomized, double-blind, placebo-controlled trial. Participants consumed a rather small amount of DHA (150 mg) and EPA (1050 mg). The researchers found an overall trend of improvement comparing fish oil to placebo. However, in the group of patients with major depression that did not also have anxiety disorder, the benefit of fish oil was clearly superior to placebo. Major depression is not an easy issue to combat so any improvement is noteworthy. The fact that improvement was seen on such a low dose of DHA is actually quite impressive.
The third study was conducted with 485 healthy adults average age 55 who had been diagnosed with age-related cognitive decline3 (a condition heading in the direction of Alzheimer’s disease). This study was a 24 week, randomized, double-blind, placebo-controlled trial. Participants were given 900 mg DHA or placebo. DHA blood levels were doubled compared to the placebo group at the end of the trial. The DHA group had improved learning and memory function. The researchers concluded that DHA “is a beneficial supplement that supports cognitive health with aging.”
Everyone should understand that DHA will accumulate in brain cells as time goes along, month after month. All of these human trials are relatively short and so benefit is good news; however, it is likely that benefits will be best on higher doses over longer periods of time.
In related animal-study news, DHA was found to:
1) Boost nerve rejuvenation4 in old rats.
2) Preserve nerve synapses5 and nerve health in Alzheimer’s disease mice.
3) Synergistically boosts phosphatidylserine activity6 in brain cell membranes, which is a key to memory and coordination.
DHA/fish oil continues to be one of the top researched nutrients around the world. Each month significant new studies are published – with no end in sight. The bottom line is fairly plain, whether young or old, don’t run low on DHA.
- ^Fish Oil Helps Depressed Elderly Women J Am Coll Nutr. Rondanelli M, Giacosa A, Opizzi A, Pelucchi C, La Vecchia C, Montorfano G, Negroni M, Berra B, Politi P, Rizzo AM.
- ^Fish Oil Helps Adults with Major Depression J Clin Psychiatry. Lespérance F, Frasure-Smith N, St-André E, Turecki G, Lespérance P, Wisniewski SR.
- ^DHA Helps Age-Related Cognitive Decline Alzheimers Dement. Yurko-Mauro K, McCarthy D, Rom D, Nelson EB, Ryan AS, Blackwell A, Salem N Jr, Stedman M; on behalf of the MIDAS Investigators.
- ^nerve rejuvenation
- ^DHA Protects Nerves in Alzheimer’s Disease Mice Biochim Biophys Acta. Oster T, Pillot T.
- ^DHA Synergistically Boosts PhosphatidylSerine Brain Signalling Prostaglandins Leukot Essent Fatty Acids. Kim HY, Akbar M, Kim YS.
Byron J. Richards, Board Certified Clinical Nutritionist