Could omega-3 fatty acids help protect women against Alzheimer’s disease? A new study from King’s College London suggests they might.
Researchers analyzed blood samples from 841 people with Alzheimer’s, mild cognitive impairment or no cognitive issues. Using mass spectrometry to measure more than 700 lipids, or fat molecules, they found a clear sex difference: women with Alzheimer’s had much lower levels of unsaturated fats, including those containing omega-3s, compared with healthy women. Men with Alzheimer’s, by contrast, showed no significant difference in lipid composition compared with healthy men.
“Women are disproportionately impacted by Alzheimer’s Disease and are more often diagnosed with the disease than men after the age of 80,” said senior author Dr. Cristina Legido-Quigley of King’s College London. “One of the most surprising things we saw when looking at the different sexes was that there was no difference in these lipids in healthy and cognitively impaired men, but for women this picture was completely different. The study reveals that Alzheimer’s lipid biology is different between the sexes, opening new avenues for research.”
The findings, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, suggest that fatty acids may play a causal role in Alzheimer’s risk. Saturated fats, often considered “unhealthy,” were higher in women with Alzheimer’s, while the fats with omega-3s were most decreased.
“Our study suggests that women should make sure they are getting omega fatty acids in their diet — through fatty fish or via supplements,” Dr. Legido-Quigley added. “However, we need clinical trials to determine if shifting the lipid composition can influence the biological trajectory of Alzheimer’s Disease.”
First author Dr. Asger Wretlind said the differences were “very striking” and noted the team is now looking at how early in life these changes may begin in women.
Experts caution that more work is needed.
“In the UK, two in three people living with dementia are women,” said Dr. Julia Dudley, Head of Research at Alzheimer’s Research UK. “While this study shows that women with Alzheimer’s had lower levels of some unsaturated fats compared with men, further work is needed. This includes understanding the mechanisms behind this difference and finding out if lifestyle changes, including diet, could have a role.”
The researchers say their results underscore the importance of studying sex-specific biology in Alzheimer’s. Future clinical trials will be needed to determine whether omega-3s can directly lower risk or slow progression in women.
This study was supported by LundbeckFonden and Alzheimer’s Research UK.