High‑Dose DHA Supplementation Fails to Boost Memory in Elderly

In a double‑blind trial involving 365 seniors, researchers tested the cognitive impact of a two‑year regimen of high‑dose docosahexaenoic acid (DHA). Participants were between 55 and 80 years old, consumed little fish, and many carried the APOE4 allele linked to Alzheimer’s risk.

The test group received DHA capsules, while a control group took identical‑looking placebo pills. Over the study period, scientists measured recall ability, problem‑solving speed, and brain imaging markers.

Even though DHA levels in the brain’s surrounding fluid rose by an average of 17 % within the first six months, the cognitive assessments showed no meaningful difference between the DHA and placebo groups. The size and shape of the hippocampus, a region vital for memory formation, remained unchanged.

These findings indicate that simply increasing DHA intake through supplements does not translate into measurable cognitive gains for older adults at risk of dementia.