UK Biobank study defines populations most likely to benefit from omega-3 interventions

The study updates the associations between blood omega-3 biomarkers and incident dementia in the framework of the UK Biobank after the recent release of metabolic biomarker data from an additional 157,000 participants.

Findings reinforce the notion that although DHA is the main omega-3 in brain tissues, other dietary omega-3 might also play a role in the development of dementia, either through conversion to DHA or, more plausibly, by providing benefits on their own.

The researchers from the Fatty Acid Research Institute, in Sioux Falls, US, conclude: “We observed that the total omega-3 status was inversely related to the risk of Alzheimer’s (Q5 vs. Q1, hazard ratio [95% confidence interval] = 0.87 [0.76; 1.00]) and all-cause dementia (Q5 vs. Q1, 0.79 [0.72; 0.87]). The strongest associations were observed for total omega-3 (and non-DHA omega-3) and all-cause dementia. In prespecified strata, we found stronger associations in men, and in those aged ≥60 years at baseline (vs. those aged 50–59). 

“Thus, in the largest study to date on this topic, we confirmed the favorable relationships between DHA and risk for dementia, and we also found evidence that non-DHA omega-3 may be beneficial. Finally, we have better defined the populations most likely to benefit from omega-3-based interventions.”

Background

While the strength of the association of DHA intake with dementia from experimental and epidemiologic studies appears to be clinically relevant, there is the long-standing question of whether other omega-3 fatty acids may also play preventive roles in dementia.