Until now, research has shown inconsistent associations between red meat consumption and cognitive health. In the current study, researchers thus investigated the link between red meat consumption and multiple cognitive outcomes.
To do so, they analyzed data from two cohort studies in the US including a total of 133 771 participants with an average age of around 49 years old who did not have dementia at the beginning of the study. Data included assessments of diet, objective cognitive function, subjective cognitive decline, and incident dementia cases. The participants were followed for up to 43 years, with 11, 173 of them developing dementia.
Ultimately, the researchers found that participants in the highest tertile of processed red meat consumption, who ate 0.25 or more of a 3-ounce serving per day, had a 13% higher risk of developing dementia than those in the low group, consuming less than 0.1 servings per day. Processed red meats were defined as bacon, hot dogs, sausages, salami, bologna, and other products.
The researchers further found that participants in the highest tertile of processed red meat consumption had a 14% higher risk of subjective cognitive decline than those in the lowest tertile.
While consumption of unprocessed red meat did not affect dementia risk, eating one or more servings of the food per day was linked to a 16% higher risk of subjective cognitive decline than eating less than half a serving per day. Unprocessed red meat was defined as foods including beef, lamb, and hamburgers.
The researchers further found that replacing one serving per day of processed red meat with a serving of nuts and legumes was linked to a 19% lower dementia risk and 1.37 fewer years of cognitive aging. Substituting for fish and chicken was linked to a 28% and 16% lower dementia risk.
"Reducing how much red meat a person eats and replacing it with other protein sources and plant-based options could be included in dietary guidelines to promote cognitive health," said study author Dong Wang, MD, ScD, of Brigham and Women's Hospital in Boston, in a press release.
A key limitation of the study is that it primarily included data from white healthcare professionals. Further research is thus needed to assess other demographics.
Sources: Science Daily, Neurology