New research reveals that fish oil may help prevent Alzheimer’s disease in some people who are at high risk.

A clinical trial at OHSU shows significant benefits for people with a genetic predisposition to Alzheimer’s.

A clinical trial at Oregon Health & Science University shows that fish oil supplements can help adults with genetic disorders. Alzheimer’s disease death.

The study was recently published in the journal JAMA Network Open.

The results come amid claims that fish oil supplements can improve brain function in people with memory problems. The study did not find a statistically significant benefit for all older adults in general. However, among those enrolled in the study who also have a gene linked to Alzheimer’s disease, it showed a reduction in the breakdown of nerve cells in the brain.

Genetic factors and the effectiveness of fish oil

The senior co-author of the OHSU study suggested that fish oil may be beneficial for those who carry it APOE4 gene, which indicates a greater risk of Alzheimer’s disease, but not necessarily in all older people.

“Our findings showed that at three years, there was no statistically significant difference between the placebo and the fish oil group,” said Lynne Shinto, ND, MPH, professor of neurology. at OHSU School of Medicine. “I don’t think it’s harmful, but I wouldn’t say you need to take fish oil to prevent dementia.”

The study included 102 participants who were 75 years of age or older and had low blood levels of omega-3 fatty acids, which are found in fish oil. Participants underwent magnetic resonance imaging, or MRIs, of their brains when they first enrolled, and again at the end of the three-year study, to assess the extent of change in white matter lesions in the brain. These lesions can disrupt the supply of nutrients through the blood vessels to the brain, increasing the risk of dementia later in life.

Participants enrolled in the study had extensive white matter lesions but were otherwise healthy, without dementia.

Results and Outcomes

Half of the participants took fish oil supplements containing omega-3 every day while half took a soy-based placebo. Two MRIs that measured the degree of white lesions at the beginning and at the end of the study period found a slight reduction in the development of these lesions – but not enough to have a statistical difference between the two groups.

Among APOE4 carriers, however, the researchers measured a significant reduction in brain cell damage as soon as one year after treatment with fish oil, compared to the soybean oil group.

“This is the first dementia prevention trial to use the latest prevention tools, such as blood tests and brain scans, to identify not only people at high risk of dementia, but also those who are well-suited to get special treatment,” said Gene. Bowman, ND, MPH, director of clinical trials and instructor of neurology at the McCance Center for Brain Health, Massachusetts General Hospital and Harvard Medical School. The fact that the deterioration of nerve integrity was delayed in people who were given omega-3 therapy who are also at high risk for Alzheimer’s disease is remarkable, and warrants a larger trial of medicine to different people in the future.

Reference: “ω-3 PUFA for Secondary Prevention of White Matter Lesions and Neuronal Integrity in Older Adults: A Randomized Clinical Trial” by Lynne H. Shinto, Charles F. Murchison, Lisa C. Silbert, Hiroko H. Dodge, David Lahna , William Rooney, Jeffrey Kaye, Joseph F. Quinn and Gene L. Bowman, 1 August 2024, JAMA Network Open.
DOI: 10.1001/jamanetworkopen.2024.26872

Bowman previously worked at OHSU, where the clinical trial was conducted.

This study was supported by the National Institute on Aging Public Health Organizations grants R01AG043398, P30AG008017 and P30AG066518; a National Center for the Advancement of Translational Sciences NIH award to the Oregon Clinical and Translational Research Institute at OHSU, grant award UL1TR002369; and the Office of the Director of the NIH, grants S10OD021701, S10OD018224 and S10OD016356 for shared facilities located at the OHSU Center for Advanced Research. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.