Replacing processed red meat with beans and nuts may help lower dementia risk

• A recent study presented at the Alzheimer’s Association International Conference 2024 reveals that daily consumption of processed red meat, such as bacon and bologna, increases the risk of dementia by 14%.
• Replacing processed red meat with nuts and legumes can lower this risk by 20% and reduce cognitive aging by over a year.
• While a heart-healthy diet is beneficial, no single food has been proven to prevent or cure Alzheimer’s disease, highlighting the complexity of addressing dementia through diet alone.

According to a new study, individuals who consume at least 1/4 serving of bacon, bologna, or other processed red meat daily (approximately 2 servings per week) have a higher risk of developing dementia compared to those who consume less than 1/10 of a serving daily (about 3 servings per month).

The research also indicates that replacing 1 serving of processed red meat with 1 serving of nuts and legumes, such as beans and peas, each day can reduce the risk of dementia.

The study authors recently presented their findings at the at the Alzheimer’s Association International Conference (AAIC) 2024, held in Philadelphia and online. They are yet to publish these findings in a peer-reviewed journal.

However, the caveat is that while eating a heart-healthy diet overall may help lower the risk of cognitive decline and dementia, there is no direct evidence that any single food or ingredient can prevent or treat Alzheimer’s disease or other forms of dementia.

Furthermore, given the complexity of Alzheimer’s disease , it is improbable that one food or ingredient will have a significant beneficial impact.

Nuts and legumes may protect cognitive function

The researchers monitored over 130,000 participants from the Nurses’ Health Study and Health Professionals Follow-Up Study for up to 43 years to examine the link between red meat consumption and dementia.

They identified 11,173 cases of dementia. Participants’ diets were assessed every 2 to 4 years using food-frequency questionnaires.

These questionnaires asked how often they consumed processed red meat, such as bacon (two slices), hot dogs (one), sausages or kielbasa (2 ounces or two small links), salami, bologna, or other processed meat sandwiches.

They also inquired about the consumption of nuts and legumes, including peanut butter (1 tablespoon), peanuts, walnuts or other nuts (1 ounce), soy milk (8-ounce glass), string beans, beans or lentils, peas or lima beans (1/2 cup), or tofu or soy protein.

Reported for the first time at AAIC 2024, the findings indicated that participants who consumed 1/4 serving or more of processed red meat daily had a 14% higher risk of dementia compared to those who ate less than 1/10 serving daily.

In addition, the researchers evaluated cognition using the Telephone Interview for Cognitive Status for 17,458 participants.

They found that each additional daily serving of processed red meat corresponded to an extra 1.61 years of cognitive aging for global cognition — overall cognitive function, including language, executive function, and processing—and an extra 1.69 years of cognitive aging in verbal memory, which is the ability to recall and understand words and sentences.

However, replacing 1 daily serving of processed red meat with 1 serving of nuts and legumes was associated with a 20% lower risk of developing dementia, and 1.37 fewer years of cognitive aging in global cognition.

Processed red meat a significant dementia risk factor

The researchers noted that previous studies have shown mixed results regarding the relationship between meat consumption and cognitive decline. Therefore, they closely examined how different amounts of both processed and unprocessed meat affect cognitive risk and function.

Their long-term study revealed that consuming processed red meat could be a significant risk factor for dementia.

The researchers also investigated unprocessed red meat and found no significant association between its consumption and dementia risk, including meats like hamburger, steak, or pork chops.

Heather Snyder, PhD , Alzheimer’s Association senior vice president of medical and scientific relations spoke to Medical News Today about this study, pointing out that “it’s known that eating more ultra-processed foods is bad for cognitive health, and this study adds to a growing body of evidence on this subject.”

“Processed red meat has already been shown to raise the risk of cancer, heart disease and diabetes. It may impact brain health because it has high levels of harmful substances such as nitrites (preservatives) and sodium,” explained Snyder, who was not involved in this study.

“However, it’s worth noting that there is not a single food or ingredient that, through rigorous scientific research, has been shown to cause, increase risk,  prevent, treat or cure Alzheimer’s or other dementia,” she added.

Megan Hilbert, RDN , a registered dietitian specializing in gut health nutrition, affiliated with Top Nutrition Coaching, who was also involved in the research, also emphasized that “for years now, we’ve known that eating enough processed red meat in the diet can have negative health implications like increased risk of certain cancers, increased risk of heart disease and stroke, and associations with obesity.”

However she was heartened by the “good news” that “replacing said red meat with nuts, beans/legumes, tofu, or other minimally processed soy [may potentially help] reverse that risk, and has neuroprotective effects [against] symptoms of cognitive decline.”

David Merrill, MD, PhD , a board-certified geriatric psychiatrist at Providence Saint John’s Health Center in Santa Monica, CA, and Singleton Endowed Chair in Integrative Brain Health, also not involved in this research, told MNT that:

“[The study] provides strong evidence that healthy food choices over time indeed slow the rate of brain aging, reduce the risk of developing dementias like Alzheimer’s disease, and ultimately increase the odds of achieving successful aging — free of debilitating cognitive impairment.”

It also “adds to the evidence behind limiting or ideally eliminating intake of processed red meats,” and that “[m]aking healthier dietary choices like eating nuts and beans regularly in place of processed red meat results in better outcomes with aging,” said Merrill.

How plant-based proteins benefit cardiovascular health

Hilbert added that “we aren’t 100% clear on why this association exists, but there are some theories as to why we see this increased risk.”

“First, processed meats can impact the health of our cardiovascular system which of course, supplies oxygen and nutrients to our brainm” she explained. “When this connection is frayed, our brain may not perform optimally. These processed meats also can cause excess inflammation which can contribute to poor brain health by damaging brain cells.”

“The reason nuts, seeds, beans, legumes, and soy may help reduce this risk is because nutrients in these foods can have the opposite effect on brain health. Omega-3s, antioxidants, and phytonutrients, all can keep our cardiovascular system and brain cells healthy.”

– Megan Hilbert, RDN

In conclusion, Hilbert noted that “these findings further confirm the public health message of reducing intake of processed meats in particular and adding more of these healthy plant based proteins into patients’ diets.”

“We don’t have to completely cut out meat to be healthy, but more and more research shows us that less is more, especially with processed meats,” she added.