Women with Alzheimer’s disease have significantly lower levels of omega fatty acids in their blood compared with healthy women, according to new research. The finding was not observed in men, suggesting important sex-related differences in how the disease develops.
Key Findings
An international team led by King’s College London analysed blood samples from more than 800 participants, including Alzheimer’s patients, people with mild cognitive impairment, and healthy controls. Results showed that women with Alzheimer’s had up to 20% lower levels of unsaturated fats, including omega fatty acids, than healthy women. At the same time, they displayed higher levels of saturated fats.
In contrast, men with Alzheimer’s did not show the same lipid imbalance. Researchers believe this difference could affect how the brain receives essential nutrients. “These lipids feed the brain,” explained Dr Cristina Legido-Quigley, senior author of the study published in Alzheimer’s & Dementia. She added that the findings raise the possibility that low omega levels may play a causal role in the disease, though clinical trials are needed to confirm this.
Why Women Are More Affected
Alzheimer’s is twice as common in women as in men. Factors such as longer lifespan, hormonal differences, immune responses, and even social influences like access to education are thought to contribute. The new research suggests that metabolic differences may also be critical.
Role of Diet and Omega-3
Omega-3 fatty acids are widely known for their health benefits, particularly for the brain and heart. Found in foods such as oily fish, flaxseed, chia seeds, and walnuts, they are considered essential nutrients. While past trials have shown that omega-3 supplements do not improve cognition in people already diagnosed with dementia, researchers argue that supplementation could still help delay disease onset in women with low omega levels.
Dr Legido-Quigley recommends women ensure they consume enough omega fatty acids in their diet, noting that deficiencies may start as early as the 50s.
Expert Commentary
Dr Julia Dudley of Alzheimer’s Research UK, which co-funded the study, said further work is needed to understand the mechanisms behind the sex differences and whether dietary changes could play a preventive role. “Understanding how the disease works differently in women could help doctors tailor future treatments and advice,” she said.
Recommended Intake
The NHS advises adults to eat two 140g portions of fish per week, including at least one oily fish, to meet DHA and EPA needs. Plant-based sources such as walnuts and flaxseed provide ALA, another essential omega-3.
This study highlights the need for sex-specific approaches in Alzheimer’s prevention and treatment, with diet emerging as a potential tool to reduce risk in women.
