A MAJOR study has found that women with Alzheimer’s disease have significantly lower levels of unsaturated lipids, including omega fatty acids, in their blood compared with cognitively healthy women, highlighting a potential protective role for these fats in brain health.
Alzheimer’s disproportionately affects women, particularly after the age of 80 years, yet the biological reasons remain poorly understood. To explore sex-specific lipid signatures, researchers analysed plasma samples from 841 participants in the AddNeuroMed cohort, including 306 with Alzheimer’s disease, 165 with mild cognitive impairment, and 370 cognitively healthy controls. Using lipidomics, they profiled 268 single lipids per participant and examined how lipid composition differed between men and women, while also testing for causal pathways through mediation analysis.
The results revealed significant sex differences. Three lipid modules were associated with Alzheimer’s in women but only one in men (p<0.05). In women with Alzheimer’s, families of lipids containing highly unsaturated fatty acids, including omega fatty acids, were consistently reduced, while saturated lipids were increased (q<0.05). Crucially, the effect of unsaturated phospholipids on Alzheimer’s risk was independent of cholesterol, low-density lipoprotein, or apolipoprotein B, suggesting a direct biological influence. In contrast, no such differences in lipid profiles were found between men with Alzheimer’s and their healthy counterparts.
These findings provide evidence that lipid biology in Alzheimer’s disease is sex-specific, with women showing a distinct loss of protective omega-rich unsaturated fats. While the study does not prove causality, it raises the possibility that diets rich in omega fatty acids, such as oily fish or supplements, could play a role in reducing risk, pending confirmation in clinical trials.
Reference
Wretlind A et al. Lipid profiling reveals unsaturated lipid reduction in women with Alzheimer’s disease. Alzheimers Dement. 2025;21(8):e70512.
