Processed red meats, such as bacon and deli meats, are associated with various health problems. A recent study suggests a link between high red meat consumption and increased risk of brain damage.
In research published in Neurology, Dr. Daniel Wang and colleagues found that individuals with higher processed red meat intake exhibited a 14% greater risk of dementia over four decades compared to those with minimal consumption.
The study analyzed data from over 130,000 health professionals participating in the Nurses’ Health Study and the Health Professionals Follow-Up Study. Participants completed detailed dietary surveys every two to four years, reporting their consumption of over 150 foods. Researchers also gathered health data on dementia diagnoses and conducted brief memory assessments.
“Our data indicate a correlation between higher processed red meat intake and increased risk of dementia, subjective cognitive decline, and poorer cognitive function,” explains Wang.
The scientists observed a heightened risk across all outcomes with any processed red meat consumption, increasing with higher intake. The 14% increased dementia risk represented the upper limit.
This increased risk was linked to daily consumption of at least a quarter of a 3-oz serving of processed red meat—equivalent to two bacon slices, one and a half bologna slices, or a hot dog—compared to those consuming less than a tenth of a serving.
Wang intends to continue studying these populations to better understand the impact of processed red meat on the brain and dementia. One hypothesis suggests that high saturated fat and sodium content in processed meat increases the risk of diabetes and heart disease, potentially harming the brain by raising blood pressure. Another theory focuses on compounds formed during the body’s breakdown of processed red meat, some of which promote amyloid protein clumping, a hallmark of dementia. Furthermore, nitrites in processed meats may damage DNA, leading to brain cell injury.
Previous studies on processed red meat and dementia yielded inconsistent results. Wang attributes this to smaller sample sizes, shorter follow-up periods, and less frequent dietary assessments. His team’s approach, however, “tracked changes in dietary intake over decades, a key strength of our study,” he notes.
The detailed dietary data also enabled the researchers to estimate the impact of red meat substitution on dementia risk. Replacing one daily serving of processed red meat with nuts or legumes resulted in a 19% lower dementia risk; substituting with fish was linked to a 28% lower risk; and replacing with chicken showed a 16% reduction.
The data allowed Wang’s team to compare individuals who consumed more processed red meat to those who ate more unprocessed red meat. While those consuming more unprocessed red meat showed a slightly higher dementia risk, this association was not statistically significant.
However, based on self-reported cognitive function, individuals who consumed more unprocessed red meat had a 16% higher risk of memory problems. This subjective assessment involved six to seven yes-or-no questions, such as difficulty recalling friends’ names or finding their way home.
Although not a direct dementia measure, this subjective assessment gauges memory issues and is “very sensitive,” says Wang, often detecting early signs of cognitive decline. It might therefore serve as a useful indicator for doctors. Wang plans to continue monitoring these populations to determine if these self-reported memory problems translate to dementia diagnoses on standardized testing.
“The key takeaway is that limiting red meat intake is beneficial,” says Wang. “Even a small reduction offers cognitive health advantages, especially when implemented early.”