Over the past few years, health experts have encouraged people to limit their meat consumption thanks to growing data linking processed and red meat to heart disease, type 2 diabetes, and certain kinds of cancer. But new research suggests that higher meat intake was associated with a lower risk of cognitive decline and dementia – for certain people.
Of course, details matter here. The findings only apply to a group of people with a specific genetic risk factor for Alzheimer’s disease, although this group still makes up a solid portion of the population. Prior research has also shown that a higher intake of certain meats (like processed red meat) has been associated with a higher risk of dementia, making the details of this latest study important to unpack. Here’s what neurologists and experts want you to keep in mind.
Meet the experts: Jakob Norgren, PhD, lead study author and postdoctoral researcher in the Department of Neurobiology, Care Sciences and Society at Karolinska Institutet; Aviva Lubin, MD, chief of Neurology at Episcopal Health Services; and Clifford Segil, DO, a Neurologist at Providence Saint John’s Health Center in Santa Monica, California.
What did the study find?
The study, which was published in JAMA Network Open, analysed data from 2,157 older adults who participated in the Swedish National Study on Ageing and Care, Kungsholmen (SNAC-K), for up to 15 years. The participants were at least 60 years old at the start of the study and had no dementia diagnosis.
The researchers looked at self-reported data on the participants’ diets, along with cognitive health measures. They also grouped participants by a gene called APOE, which impacts the risk of Alzheimer’s disease. (Research suggests that nearly 70 per cent of people with Alzheimer’s disease have the APOE 3/4 and APOE 4/4 genotypes.)
The team found that people with the APOE 3/4 and APOE 4/4 genotypes who consumed lower amounts of meat (about 200g a week) had more than twice the risk of dementia compared to those who consumed higher amounts. But that increased risk of cognitive decline and dementia wasn’t seen in the participants who ate the most meat (or 30.6 ounces per week).
People who ate more meat overall had slower cognitive decline and a lower risk of dementia, but only if they had those APOE 3/4 and APOE 4/4 genotypes.
OK, but… why? It’s not entirely clear, but there is a theory.
‘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,’ says Jakob Norgren, PhD, lead study author and postdoctoral researcher in the Department of Neurobiology, Care Sciences and Society at Karolinska Institutet.
Do the findings apply to people without these APOE genotypes?
There was no link in this study between the amount of meat people ate and dementia risk if they didn’t have the APOE 3/4 and APOE 4/4 genotypes. But about 1 in 4 Americans carries the APOE 3/4 or 4/4 genotype, according to Norgren.
Each person inherits two APOE genes, one from each parent, giving six possible combinations, he explains. Norgren says that the majority of people with Alzheimer’s disease carry the APOE 3/4 and APOE 4/4 genotypes.
What’s the ideal meat for lowering dementia risk?
Red meat – especially processed red meat – has been linked with a higher risk of dementia, making this a tricky area to navigate. Processed red meats can look like cured or salted meats, such as bacon, sausage, pepperoni, or deli meats.
‘It is primarily processed meat that has been associated with an increased risk of dementia,’ Norgren says. ‘In our study, higher intake of unprocessed red meat was associated with a lower risk of dementia, regardless of APOE genotype.’
Still, his team’s main analysis focused on a person’s total meat consumption, which was about 70 per cent unprocessed meat. So, chicken, fish, pork, and even lean beef may all be on the table.
What to take away from the findings, according to doctors
Neurologists are hesitant to recommend that everyone run out and eat more meat in an effort to lower their dementia risk.
‘As neurologists, we’re always trying to find ways to reduce a patient’s risk for developing dementia and subsequently slow the rate of cognitive decline,’ says Aviva Lubin, MD, chief of Neurology at Episcopal Health Services. ‘If these findings could be generalised, then it would add to our available treatment plans.’
But Lubin points out that most patients who are being evaluated for dementia aren’t tested for APOE genotypes. Therefore, she says, ‘it’s difficult to apply the results to regular office practice.’
When it comes to diet, ‘I would continue to prioritise healthy food choices to include fish and poultry over red meat as we age,’ says Clifford Segil, DO, a neurologist at Providence Saint John’s Health Centre in Santa Monica, California. ‘This research is interesting, but our knowledge of the health benefits from eating fish and chicken over red meat is well established.’
Ultimately, more research needs to be done before doctors recommend that patients start chowing down on steak to lower their risk of dementia.
