The research
Researchers at Karolinska Institutet published a study in JAMA Network Open on April 2, 2026, that followed more than 2,100 adults aged 60+ without dementia for up to 15 years. They tracked self-reported dietary habits and cognitive health while accounting for age, sex, education, and lifestyle.
First author Jakob Norgren explained they tested the hypothesis that people with APOE 3/4 and 4/4 gene variants—which increase Alzheimer's risk—might benefit from higher meat intake because APOE4 is evolutionarily old and may have arisen when human ancestors ate more animal-based diets.
Among participants with these gene variants who consumed lower amounts of meat, dementia risk was more than double compared to those without the variants. However, this elevated risk disappeared in the highest meat intake group, where median consumption was about 870 grams per week adjusted to 2,000 daily calories. Those with APOE 3/4 or 4/4 who ate the most meat had significantly slower cognitive decline and lower dementia risk.
Assistant professor Sara Garcia-Ptacek noted that a lower proportion of processed meat in total meat consumption was associated with lower dementia risk regardless of APOE genotype. The researchers also found people with these gene variants who consumed more unprocessed meat had significantly lower risk of death from any cause.
Why it matters
This research suggests dietary advice for brain health may need to be personalized based on genetic profile. About 30% of people in Sweden carry these APOE variants, and among those diagnosed with Alzheimer's, nearly 70% have one of them. The findings challenge conventional dietary recommendations and indicate that for this genetically defined subgroup, higher meat consumption might help modify dementia risk.
Jakob Norgren emphasized: "Our findings suggest that conventional dietary advice may be unfavourable to a genetically defined subgroup of the population. For those who are aware that they belong to this genetic risk group, the findings offer hope; the risk may be modifiable through lifestyle changes."
What you can do
If you know you carry APOE 3/4 or 4/4 variants through genetic testing, discuss these findings with a healthcare professional. Consider focusing on unprocessed meats rather than processed varieties if adjusting your diet. Remember this is an observational study that cannot prove cause and effect—clinical trials are needed to confirm whether dietary changes directly influence dementia risk.
Source: ScienceDaily Mind & Brain
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