Meat Consumption Linked to Lower Dementia Risk in Those with Alzheimer’s Gene
A new Swedish study suggests that older adults with a higher genetic risk of developing Alzheimer’s disease may experience slower cognitive decline and a lower risk of dementia with relatively high meat intake. However, the type of meat consumed appears to matter, with processed meats potentially increasing risk.
The APOE4 Gene and Alzheimer’s Risk
The research focuses on individuals carrying the APOE4 genetic variant, a gene that significantly raises the risk of Alzheimer’s disease. Approximately 30 percent of the Swedish population carries the APOE 3/4 or APOE 4/4 genotype, and nearly 70 percent of people with Alzheimer’s disease have one of these genotypes. Karolinska Institutet researchers initiated this study following a call for further investigation from the Swedish Food Agency regarding the connection between meat intake and dementia development.
Can Meat Protect the Brain?
The study, published in JAMA Network Open, tracked more than 2,100 participants in the Swedish National Study on Aging and Care, Kungsholmen (SNAC-K) for up to 15 years. All participants were 60 or older and had no dementia diagnosis at the study’s start. Researchers analyzed self-reported dietary information alongside cognitive health measures, adjusting for factors like age, sex, education, and lifestyle.
The study categorized red meat (beef and pork) and poultry (chicken and turkey) as unprocessed, while deli meats, bacon, and sausage were classified as processed. Participants were grouped based on their total meat consumption, ranging from approximately 1 ounce to 4.5 ounces per day.
Researchers found that among those with the APOE 3/4 or 4/4 genotype, higher meat consumption was associated with slower cognitive decline. The highest meat intake group (median 870g per week) showed significantly slower cognitive decline compared to those with lower intake within the same genetic group. Neuroscience News reports that at lower meat intake levels, APOE4 carriers had more than twice the risk of dementia compared to non-carriers, but this increased risk disappeared in the highest meat-consumption tier.
The Role of Processed vs. Unprocessed Meat
While higher unprocessed meat intake appeared protective for those with the APOE4 gene, the study consistently found that a higher proportion of processed meat in the diet was linked to a higher risk of dementia across all participants, regardless of their genetic profile.
Experts suggest this difference may be due to additives like nitrates found in processed meats, which can have damaging effects on the brain. Hussein Yassine, MD, a professor of neurology at the USC Keck School of Medicine, emphasizes that unprocessed meat provides beneficial nutrients like protein, iron, zinc, B vitamins, and choline.
Study Limitations and Future Research
It’s important to note that this was an observational study, meaning it cannot prove cause and effect. The findings suggest an association, but other factors could be at play. The study also relied on self-reported food diaries, which can be subject to inaccuracies.
Researchers hypothesize that the protective effect of meat in APOE4 carriers may be linked to evolutionary history. Jakob Norgren, PhD, the study’s first author, suggests that the APOE4 gene is the oldest variant and may have evolved during a time when our ancestors consumed a more animal-based diet.
Expert Advice on Lowering Alzheimer’s Risk
Regardless of genetic predisposition, experts recommend a holistic approach to brain health, including:
- Maintaining a healthy heart through blood pressure and cholesterol management.
- Regular physical activity.
- Social engagement and cognitive stimulation.
The MIND diet, which emphasizes leafy greens, berries, whole grains, fish, poultry, nuts, and olive oil while limiting red meat, processed foods, and sweets, is also recommended.