Mind

Omega-3s, probiotics improve cognition

DHA reduces chances of dementia

A new series of studies and reviews reveals DHA reduces chances for cognitive decline and dementia, including Alzheimer’s disease (AD). In the first study, 1,135 long-term users of omega-3 supplements, who started without dementia, were 64 percent less likely than non-users to have developed AD over six years of follow-up.

In a review of 48 studies covering 103,651 participants, omega-3s reduced chances for any dementia by 20 percent, with the greatest benefit from DHA. In a meta-analysis of 18 studies covering 46,548 adults, DHA reduced chances for dementia 27 percent, and for AD, 24 percent. Adults older than 65 years who regularly took omega-3s were 23 percent less likely to have cognitive decline than non-users.

In an analysis covering 27,161 healthy individuals and 3,797 with cognitive decline, overall, each 100 mg increase in the omega-3s EPA or DHA per day reduced chances by an average of 9 percent.

Reference: American Journal of Clinical Nutrition; 2023, Vol. 117, No. 6, 1096-1109

Probiotics improve cognitive function in AD

This review of 10 worldwide, placebo-controlled probiotics studies covered 715 participants, aged 50 to 100, some healthy, others with cognitive decline. Overall, those in the probiotics groups were 36 percent less likely to have developed cognitive decline over the various follow-up periods.

Probiotics also promoted cognitive function in those with cognitive impairment, especially in AD, compared to placebo. In general, multiple probiotics strains improved cognition more than single strains. The best outcomes came in studies lasting at least 12 weeks with doses of probiotics above one-billion colony-forming units.

The probiotics strains in the studies included lactobacillus (L): -acidophilus, -casei, -fermentum, -helveticus, and -rhamnosus; and bifido (B): -bifidum, -bifidus, -breve, -infantis, and -longum.

Reference: Nutrition Reviews; 2023, Vol. 81, No. 9 1091-1104