Meat Intake May Benefit Some at Higher Dementia Risk

A study published in JAMA Network Open suggests that diet (and specifically meat consumption) may play a different role in brain health depending on a person’s genetics. Investigators focused on a gene called APOE, which is known to influence the risk of developing Alzheimer’s disease and other forms of dementia.

The study followed more than 2,100 adults aged 60 and older enrolled in the Swedish National Study on Aging and Care-Kungsholmen (SNAC-K) study for up to 15 years. The mean age of participants was 71 years, and most (60%) were women. None had dementia at the start. About a quarter of participants had higher-risk versions of the APOE gene (called ε3/ε4 or ε4/ε4), which are typically linked to a greater likelihood of cognitive decline over time.

Dietary intake was evaluated using 98-item food-frequency questionnaires, with the main exposure being total meat consumption and the secondary exposure being the ratio of processed to unprocessed meat.

Investigators found something surprising: Among people with these higher-risk genetic profiles, those who consumed more total meat had slower cognitive decline and a lower risk of developing dementia compared with those who ate less meat. In fact, at higher levels of meat intake, the usual increased risk associated with these genes appeared to be reduced.

“This study tested the hypothesis that people with APOE 3/4 and 4/4 would have a reduced risk of cognitive decline and dementia with higher meat intake, based on the fact that APOE4 is the evolutionarily oldest variant of the APOE gene and may have arisen during a period when our evolutionary ancestors ate a more animal-based diet,” explained lead investigator Jakob Norgren, Ph.D., a researcher at the Department of Neurobiology, Care Sciences and Society, Karolinska Institutet.

However, this pattern did not apply to people with other APOE genotypes. In those individuals, meat consumption did not appear to significantly affect cognitive decline or dementia risk. This suggests that dietary needs may differ depending on genetic background — a concept known as personalized nutrition.

The type of meat also mattered. A higher proportion of processed meats (such as deli meats or sausages) was associated with a higher risk of dementia across all groups, regardless of genetics. In contrast, unprocessed meats (like fresh red meat or poultry) did not show this negative association.

While these findings are promising, they don’t mean that everyone should increase meat consumption. The study shows an association, not proof of cause and effect, and dietary recommendations still need to consider overall health, including heart health and other conditions.

Investigators noted some limitations, including a potential survival bias, as in the selection of participants included in the analysis may be particularly resilient. Additionally, generalizability was limited, as most people were of Northern European ancestry. Lastly, there may have been some errors in self-reported dietary data, but the team doesn’t believe that would have been enough to introduce bias for APOE interactions.

For patients, the key takeaway is that one-size-fits-all nutrition advice may not apply to everyone, especially when it comes to brain health. Genetics, diet quality and lifestyle all interact in complex ways. If you have concerns about cognitive health or dementia risk, it’s important to talk with your health care provider about a personalized approach.

“There is a lack of dietary research into brain health, and our findings suggest that conventional dietary advice may be unfavorable to a genetically defined subgroup of the population,” said Norgren. “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.”