Research has revealed new insights into why women are at a higher risk for Alzheimer’s disease compared to men. A study led by researchers at King’s College London suggests that levels of omega-3 fatty acids, a type of healthy unsaturated fat, may play a significant role in this disparity. The analysis found that women diagnosed with Alzheimer’s exhibited notably lower levels of these beneficial lipids, despite generally having higher omega-3 levels than men.
The investigation involved a comprehensive examination of lipid libraries from 841 participants across six European countries. Participants with Alzheimer’s demonstrated significantly elevated levels of unhealthy saturated fatty acids and diminished levels of omega-3 compared to those with sound cognitive health or mild cognitive impairment. This discrepancy highlights potential sex-specific differences in how fatty acid metabolism affects the disease.
The findings challenge previous notions that primarily focused on tau tangles and amyloid plaques, which are well-known hallmarks of Alzheimer’s. Instead, this study brings attention to the role of lipid metabolism in the disease’s progression. According to a recent Lancet Commission for Dementia, approximately 7 percent of Alzheimer’s risk can be attributed to low-density lipoprotein (LDL), a type of cholesterol-carrying lipoprotein. This may help explain why women develop Alzheimer’s at nearly twice the rate of men.
Cristina Legido-Quigley, a pharmaceutical scientist involved in the study, emphasized the importance of omega-3 in women’s diets, suggesting that they should consider incorporating fatty fish or supplements. “However, we need clinical trials to determine if shifting the lipid composition can influence the biological trajectory of Alzheimer’s disease,” she stated.
The research analyzed hundreds of individual lipids transported in the blood by lipoproteins such as LDL and high-density lipoprotein (HDL). In women, various lipids were associated with Alzheimer’s and cognitive impairment. In contrast, these patterns were not observed in men, suggesting a complex interplay between sex and lipid levels in the context of Alzheimer’s.
Julia Dudley, Head of Research at Alzheimer’s Research UK, who did not participate in the study, acknowledged the need for further investigation. “While this study shows that women with Alzheimer’s had lower levels of some unsaturated fats compared with men, further work is needed,” she remarked. Understanding the underlying mechanisms and exploring potential lifestyle changes, including diet, could prove essential in addressing this pressing health issue.
Historically, brain aging research has suffered from significant bias regarding sex differences. In 2019, only 5 percent of published studies in neuroscience or psychiatry examined the influence of sex. Furthermore, many drug trials for Alzheimer’s do not account for these differences, leaving critical gaps in understanding why women are more prone to develop the disease.
As women tend to live longer than men, even older men have a lower likelihood of developing Alzheimer’s compared to their female counterparts. “Understanding how the disease works differently in women could help doctors tailor future treatments and health advice,” Dudley added.
The study, which sheds light on the potential role of omega-3 fatty acids in women’s Alzheimer’s risk, was published in the journal Alzheimer’s & Dementia. With more research needed, this investigation could pave the way for new treatment approaches and dietary recommendations that may help mitigate the impact of this devastating disease.
