Keep your red meat to these limits to protect your brain health, experts say

Getting protein from plants such as beans, legumes and nuts instead of red meat may help protect your cognitive health, according to a new study. (Spencer Platt/Getty Images/File via CNN Newsource)

Reducing your red meat consumption could have many positive impacts — on your heart, the environment, and maybe even on your long-term cognitive health, according to a new study.

Those who ate a quarter of a serving or more of processed red meats — such as bacon, bologna and hot dogs — had a 13 per cent higher chance of developing dementia than those who had less than one-tenth of a serving per day, according to a study published Wednesday in the journal Neurology.

A serving of red meat is usually around 3 ounces (85 grams), which would be either two slices of bacon, 1.5 slices of bologna or one hot dog, according to a news release on the study.

Researchers also found that an extra daily serving of processed red meat on average was associated with a 1.6-year acceleration in brain aging, according to the study.

The study methods are observational, meaning that researchers can’t say for sure that the processed red meats are causing the dementia, only that there is an association between the two. But investigation into the connection will continue, said one of the study’s authors, Dr. Daniel Wang, an assistant professor in the department of nutrition at the Harvard T.H. Chan School of Public Health.

“Large, long-term cohort studies are essential for investigating conditions like dementia, which can develop over decades,” Wang said in a news release. “We are continuing to piece together this story to understand the mechanisms causing dementia and cognitive decline.”

Why the meat you eat affects your brain

The connection between red meat and cognitive health hasn’t been studied thoroughly, but researchers have found associations with many other health outcomes, including cardiometabolic diseases, cancers and premature death, said Dr. Mingyang Song, associate professor of clinical epidemiology and nutrition at the Harvard T.H. Chan School. He was not involved in the new research.

“In particular, processed red meat shows the strongest association due to its high content in salt, heme iron, and harmful additives used for processing,” Song said in an email.

“Also, the inflammatory response and metabolic disturbances (eg, insulin resistance) associated with high red meat consumption may also play a role,” he added in an email.

For this study, researchers analyzed data from more than 133,000 people at an average age of 49 from the Nurses’ Health Study and Health Professionals Follow-Up Study. The data included detailed health information surveyed over a long period of time, including participants’ diets, and was updated every two to four years, according to the study.

More than 11,000 study participants were diagnosed with dementia within a 43-year window.

There are theories as to why red meat might pose a particular risk to cognitive health. Red meat has a high amount of saturated fat and yields an organic compound linked to cardiovascular disease, and the two together may damage the nervous system, which worsens cognitive decline, Song said.

Processed red meat also has higher levels of substances such as nitrites, N-nitroso compounds and sodium, which pose additional risks to cognitive decline, said the study’s lead author, Yuhan Li, a research assistant in the Channing Division of Network Medicine at Brigham and Women’s Hospital in Boston.

Nitrites are ingredients often used in curing meats and have been linked to health concerns, and N-nitroso compounds are also found in cured meats and have been linked to cancer.

This latest study is important for emphasizing how the food you eat affects the way your brain ages, Wang said in the news release.

“Dietary guidelines tend to focus on reducing risks of chronic conditions like heart disease and diabetes, while cognitive health is less frequently discussed, despite being linked to these diseases,” he said. “We hope our results encourage greater consideration of the connection between diet and brain health.”

Limiting the red meat you eat

Reducing the amount of red meat you eat could be an important part of caring for your long-term health, according to the study.

Replacing red meat with plant-based protein sources such as nuts and legumes was associated with a 19 per cent lower risk of dementia and 1.37 fewer years of cognitive aging, according to the study.

The American Institute for Cancer Research recommends limiting your red meat to three portions a week and eating little if any processed red meat.

While making specific changes may help your health, the overall quality of a person’s diet is the main priority, Song said in an earlier CNN article.

If you want to cut back and eat in a more nutrient-dense way, it might be time to look into the Mediterranean diet –– which is more of a lifestyle than a restrictive diet.

It focuses on eating fruits, vegetables, grains, olive oil, nuts and seeds, and the occasional piece of fish while also focusing on social connection and physical activity.