Findings suggest diet may offset risks for APOE4 carriers, but experts caution that scientists must conduct more trials.

TheDigger Intelligence Unit

Genetics and Alzheimer’s Risk

The APOE gene strongly influences Alzheimer’s disease risk. About 30 per cent of Swedes carry APOE 3/4 or 4/4, and nearly 70 per cent of Alzheimer’s patients have these combinations. These variants can increase risk up to fifteen-fold compared to the most common genotype.

Why Meat Intake Was Studied

Researchers hypothesised that APOE4, the oldest evolutionary form of the gene, may have developed when humans relied more heavily on animal‑based diets. This led them to test whether meat consumption could influence dementia risk among carriers of APOE4.

Long-Term Swedish Study

Researchers tracked more than 2,100 adults aged 60 and above, all dementia-free at the start, for up to 15 years. Participants reported their dietary habits, and researchers compared these with measures of cognitive health, accounting for age, sex, education, and lifestyle.

Meat Consumption and Dementia Outcomes

Among those with APOE 3/4 and 4/4, eating little meat more than doubled their dementia risk. However, when participants ate the most meat—about 870 grams per week—their elevated risk disappeared. These participants showed slower cognitive decline and lower dementia rates.

Processed vs Unprocessed Meat

The type of meat plays a role. When people ate less processed meat, they reduced their risk of dementia across all genetic groups. Eating more unprocessed meat also correlated with a lower risk of death from any cause among APOE4 carriers.

Broader Health Implications

Beyond brain health, people who ate more unprocessed meat appeared to improve their overall survival rates if they were genetically vulnerable, suggesting these potential benefits extend beyond dementia prevention.

Limitations and Next Steps

Researchers emphasise that their study was observational and cannot prove cause and effect. They stress the need for clinical trials to confirm whether dietary changes directly influence dementia risk. Experts could tailor future dietary recommendations based on genetic profiles.

Understanding the APOE Gene

Apolipoprotein E helps transport cholesterol and fats in the body. Its three variants—epsilon 2, 3, and 4—affect Alzheimer’s and cardiovascular risk differently. While APOE4 significantly raises risk, APOE2 lowers it. Each person inherits two copies, resulting in six possible genotypes.