
Higher intake of red meat, particularly processed red meat, has been associated with an increased risk of developing dementia and poorer cognition. Reducing red meat consumption could be included in dietary guidelines to promote cognitive health. More research is needed to assess the generalizability of these findings to populations with diverse ethnic backgrounds.
Dementia is a general term used to describe a range of symptoms that affect memory, thinking, and social skills to a degree that is severe enough to interfere with daily life.
It is not a specific disease, but rather a collection of symptoms caused by a variety of brain diseases, with Alzheimer’s disease being the most common form.
Symptoms of dementia include memory loss, difficulty communicating and performing daily tasks, personality changes, and confusion. The risk of dementia increases with age, but it is not a normal part of aging.

There is growing evidence that diet plays an important role in cognitive health and the risk of developing dementia.
Diets rich in fruits, vegetables, whole grains, fish and healthy fats, such as the Mediterranean diet, have been associated with a lower risk of cognitive decline.
In contrast, a diet rich in ultra-processed foods, sugars, saturated fats and processed meats may increase the risk of neurodegenerative diseases.
Crucial nutrients such as antioxidants and omega-3 fatty acids, found in whole foods, help protect the brain from inflammation and oxidative damage, factors that contribute to the development of dementia.

Processed red meat refers to meats that have been modified through methods such as smoking, curing, fermenting, or adding preservatives to improve flavor or extend shelf life.
Common examples of processed red meat include sausages, bacon, ham, salami, corned beef, and dried meat (such as beef jerky, which is salted and dried).
These products often contain high levels of sodium, preservatives, and other additives, which are all factors associated with negative health impacts, including an increased risk of cardiovascular disease and, as some studies suggest, dementia.

Ultra-processed foods are those that undergo a series of industrial processes and contain ingredients that are rarely used in home cooking, such as colorings, flavorings, emulsifiers, and other additives to enhance flavor, texture, or shelf life.
They are generally low in nutritional value and high in sugars, saturated fats, and sodium. Examples of ultra-processed meats include chicken nuggets, hamburgers, industrial sausages, and mortadella.
In addition to being highly processed, these products are generally less healthy due to their high content of salt, trans fats, and empty calories, and have been linked to a variety of health problems, including obesity, heart disease, type 2 diabetes, and potentially an increased risk of cognitive decline.

In contrast, unprocessed meat is meat that is consumed in its natural state or with minimal processing, such as fresh cuts of beef, pork, or chicken.
Ultra-processed meat is often criticized for its high salt, saturated fat, and preservative content, which may be linked to a number of health problems.
Previous studies on the relationship between red meat intake and cognitive health have yielded mixed results. A recent study, conducted by scientists at the Broad Institute of MIT and Harvard, sought to investigate the association between red meat consumption and various cognitive outcomes.
The goal was to better understand whether and how consumption of red meat, both processed and unprocessed, might affect cognition and the risk of developing dementia.
This prospective cohort study analyzed data from two large cohort studies in the United States: the Nurses' Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS).
Participants, all free of dementia at baseline, had their diets assessed using semi-quantitative food frequency questionnaires. The calculation for the daily amount of meat consumed was:
1 standard portion = 50 grams
0.50 standard portion = 25 grams
0.25 standard portion = 12.5 grams
0.10 standard portion = 5 grams

The dementia analysis included 133,771 individuals, of whom 65.4% were women, with a mean baseline age of 48.9 years. For the assessment of objective cognitive function, 17,458 women were included, with a mean age of 74.3 years at baseline.
The analysis of subjective cognitive decline (SCD) included 43,966 participants, of whom 77.1% were women, with a mean baseline age of 77.9 years.
Cases of dementia were identified over several years of follow-up, allowing detailed observation of cognitive changes.
Cognitive function was assessed through telephone interviews to measure cognitive status objectively and through subjective reports of the participants themselves about their cognitive decline, providing a comprehensive view of the impact of diet on mental health over time.
The results indicated that the consumption of processed or ultra-processed red meat was associated with a higher risk of dementia and cognitive decline.
Participants who consumed 0.25 servings or more of processed red meat per day had a 13% higher risk of developing dementia and a 14% higher risk of subjective cognitive decline compared with those who consumed less than 0.10 servings per day.
In addition, higher consumption of processed red meat was associated with accelerated cognitive aging, affecting both global cognition and verbal memory.
For unprocessed red meat, those who consumed one serving or more per day had a 16% higher risk of subjective cognitive decline compared with those who consumed less than 0.50 servings per day.

One of the most interesting findings of the study was that replacing a portion of processed red meat with healthier foods, such as nuts and legumes, was associated with a significant reduction in the risk of dementia and cognitive decline.
Specifically, this substitution was associated with a 19% lower risk of dementia and slower cognitive aging.
This study suggests that consumption of red meat, especially processed meat, may be associated with increased risks of dementia and cognitive decline.
As a result, reducing red meat consumption may be considered in dietary guidelines to promote cognitive health. However, it is important to note that more research is needed to confirm these findings in diverse populations and to fully understand the mechanisms underlying these associations.
READ MORE:
Long-Term Intake of Red Meat in Relation to Dementia Risk and Cognitive Function in US Adults
Yuhan Li, Yanping Li, Xiao Gu, Yuxi Liu, Danyue Dong, Jae Hee Kang, Molin Wang, Heather Eliassen, Walter C. Willett, Meir J. Stampfer, and Dong Wang
Neurology, February 11, 2025 issue 104 (3)
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