Eating lots of fatty fish such as salmon, mackerel and sardines could help ward off Alzheimer’s disease in women, a study has suggested.
Researchers at King’s College London examined blood samples from 841 people, including 306 with Alzheimer’s. They found a noticeable loss of unsaturated fats, including those that contain omega fatty acids, in the blood of women who had Alzheimer’s compared with healthy women.
There was no difference between these fat molecules in men with or without Alzheimer’s.
The researchers said this difference could help further knowledge about why women are more likely than men to be diagnosed with Alzheimer’s.
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The research, published in the journal Alzheimer’s and Dementia, suggests that women could protect against Alzheimer’s by increasing their intake of omega-3, found in fatty fish or taken as daily supplements.
Cristina Legido-Quigley, from King’s College London, senior author of the study, said: “Women are disproportionately impacted by Alzheimer’s disease and are more often diagnosed with the disease than men after the age of 80.
“One of the most surprising things we saw when looking at the different sexes was that there was no difference in these lipids [fats] 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. Our study suggests that women should make sure they are getting omega fatty acids in their diet — through fatty fish or via supplements.
“However, we need clinical trials to determine if shifting the lipid composition can influence the biological trajectory of Alzheimer’s disease.”
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Alzheimer’s is the leading cause of dementia, which affects about a million people in the UK, two thirds of whom are women.
Asger Wretlind, also from King’s College London and first author of the study, said: “Although this still warrants further research, we were able to detect biological differences in lipids between the sexes in a large cohort, and show the importance of lipids containing omegas in the blood, which has not been done before.
“The results are very striking and now we are looking at how early in life this change occurs in women.”
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Julia Dudley, head of research at Alzheimer’s Research UK, which funded the study along with LundbeckFonden, said: “In the UK, two in three people living with dementia are women.
“This could be linked to living longer, or other risk factors like social isolation, education, or hormonal changes from the menopause being at play. 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.”
In a separate study, published in the British Journal of Ophthalmology, researchers from Hong Kong found that a higher consumption of omega-3 fatty acids was associated with a lower risk of short-sightedness in children. They examined data on 1,005 children, aged between six and eight, that included their eyesight and diet.
