Higher intake of processed red meat is associated with a 15-percent higher risk of dementia, according to new research presented at AAIC.
As people age, cognitive function tends to decline. In some people, this process happens faster than others. Mounting research points to the idea that highly processed foods with lots of calories, salt, fat and added sugars — think: sugary sodas, grocery store birthday cake, fast food burgers and fries — may cause older adults’ cognitive abilities to decline faster. New data from the Nurses’ Health Study, presented at the 2024 Alzheimer’s Association International Conference in Philadelphia, found that eating more red meat, especially processed types, might increase the risk of dementia and worsen cognitive abilities.
The study suggests that swapping out processed red meat for nuts and legumes could lower the risk of dementia. The findings build on past research, including a Brazilian study of more than 10,000 participants, which showed similar findings as to the negative brain health impacts of ultra-processed foods, presented at AAIC in 2022.
In Nurses’ Health study into red meats, over 38 years, researchers tracked 6,856 cases of dementia. They found that people who ate at least 0.25 servings of processed red meat per day had a 15-percent higher risk of developing dementia compared to those who ate less than 0.10 servings daily. The study also linked higher intake of processed red meat to faster cognitive aging and poorer verbal memory.
Heather M. Snyder, PhD, from the Alzheimer’s Association, emphasized that the findings support eating a healthier diet with less processed food to help lower the risk of cognitive decline. The study involved evaluating participants’ diets every two to four years and tracking dementia cases through self-reports and death records in 87,424 individuals without Parkinson’s, dementia, stroke, or cancer at the start.
The study also found that eating at least 0.25 servings of processed red meat per day was linked to a 14 percent higher chance of subjective cognitive decline. Moreover, consuming at least 1.00 serving of unprocessed red meat daily, compared to less than 0.50 servings, was linked to a 16-percent higher likelihood of subjective cognitive decline.
Hungry for Better Brain Health? A Neurobiologist Says Steer Clear of These Foods
Causal links between dietary habits and health outcomes can be an extremely difficult thing to study in the long term. Yuhan Li, the study’s lead author, noted that while previous studies have had mixed results on the connection between meat consumption and cognitive decline, this study’s long-term data show that processed red meat could be a significant risk factor for dementia.
“Study results have been mixed on whether there is a relationship between cognitive decline and meat consumption in general, so we took a closer look at how eating different amounts of both processed and unprocessed meat affects cognitive risk and function,” Li said in a statement. “By studying people over a long period of time, we found that eating processed red meat could be a significant risk factor for dementia. Dietary guidelines could include recommendations limiting it to promote brain health.”
Li also noted that processed red meat may be bad for brain health due to “high levels of harmful substances such as nitrites [preservatives] and sodium.” It’s also a driver of other health issues that are closely linked to dementia, including heart disease and diabetes, according to Li.
The bottom line? Diet and dementia are interconnected — and diet is something most people can, at least to some extent, control and change. The study also found that replacing one serving per day of processed red meat with nuts and legumes was associated with a 23 percent lower risk of dementia and 1.37 fewer years of cognitive aging. Additionally, this swap was linked to 20-percent lower odds of subjective cognitive decline.