People who eat a lot of processed red meat, such as sausages, bologna or bacon, have a higher risk of developing dementia later in life. It is the main conclusion of an article that has just been published. The risk of dementia was measured from a group of 133,771 people with an average age of 49 years at the start of the study, who were followed for up to 43 years. Of the initial group, 11,173 people developed the disease.
As a percentage, people who were in the group that ate the most processed red meat, starting with about two servings (just under 100 grams) per week, had a 13% higher risk of dementia than those who ate the least. three servings a month. Although the study is observational and cannot establish a cause and effect relationship, the results suggest that, in a country like Spain, the consumption of processed red meat and its replacement with legumes or chicken would reduce cases of dementia by tens of thousands .
In the same study, no significant association was found between consumption of red meat, such as pork or beef steaks, with dementia risk or other objective measures of cognitive decline. An increase of 16% in the subjective risk of cognitive deterioration (measured with a questionnaire completed by the participants themselves) was found for people who consumed seven servings of meat a week or more compared to those who consumed less than three. Although their results do not observe significant harm from unprocessed red meat, the study’s lead author, Dong Wang, from Brigham and Women’s Hospital in Boston, points to the risk factors of its consumption: “It has high levels of saturated fat and , in previous studies, has been seen to increase the risk of type 2 diabetes and heart disease, both related to poorer brain health.”
One of them is to think about what you want to achieve instead of focusing on what you want to avoid. Since what you eat is limited, instead of restricting red meat, processed or not, you can think about incorporating more healthy foods to replace it. The authors of the study analyzed the result of replacing a daily serving of processed red meat with other foods. If it was changed to fish, a 28% reduction in the risk of dementia was estimated, 19% in the case of nuts and legumes, and 16% with chicken.
Jordi Salas-Salvadó, professor of Nutrition at the Rovira i Virgili University, who has not participated in the study, is not surprised by the results. “When talking about cardiovascular disease, there is enormous evidence, but in dementia and cognitive impairment, the mechanisms are very similar. Red meat has a lot of saturated fats and this increases cholesterol, which has many effects on cardiovascular risk factors and favors the accumulation of arteriosclerosis plaque, but it also has direct effects on neurotrophic factors. [que promueven la supervivencia y el desarrollo de las neuronas]”he explains. “Meat, not just processed meat, has carnitine, which is associated with an increase in TMAO, which is a molecule produced by bacterial flora and, in addition to increasing the risk of cardiovascular disease or arteriosclerosis, it affects the expression of multiple proteins. that intervene in the neuronal synapse,” he adds.
The study authors also offer some mechanisms that would explain why excessive red meat consumption can damage the brain. In other works it has been observed that these foods can induce insulin resistance, which affects cortical activity, and is associated with excessive production of insulin in the pancreas. This is related to the accumulation of amyloid beta protein in the brain, one of the mechanisms related to Alzheimer’s. Regarding processed meat, they point out the presence of compounds such as nitrites, used to improve the conservation or flavor of products such as ham or sausages, which can induce oxidative stress and promote inflammation, causing neurotoxic effects.
The study published in Neurology Also remember that previous studies had obtained results that do not coincide with yours. with participants from the UK Biobank observed that an increase of 25 grams per day in processed meat consumption was associated with a 44% increase in the risk of dementia and a 52% increase in the risk of Alzheimer’s. However, that same study noted that higher consumption of unprocessed red meat appeared to reduce the risk of dementia and Alzheimer’s. Another study, with 2,622 participants, observed no association between the consumption of sausages and memory impairment or Alzheimer’s, something that Wang and his colleagues attribute, speculatively, to the average age of the volunteers, 81.2 years, making them They were too old to see that association. Regarding the British study, they suggest that the follow-up time, of less than 8 years, and that the participants only had an initial evaluation of their diet, may explain their data.
Wang believes that his results indicate that the recommendation “reducing the amount of red meat a person eats and replacing it with other sources of protein and vegetables could be included in guidelines for diets that promote cognitive health,” although he acknowledges that more research is needed. to confirm these findings in more diverse groups. Participants in this study came from two US cohort studies comprised of healthcare professionals. Salas Salvadó agrees that “we must reduce the consumption of processed foods, which are providing us with amounts of salt, saturated fats, sugars and other substances that are harmful, and also reduce the consumption of red meat and try to consume more fruits, vegetables, legumes, nuts, olive oil and everything that is typical of the Mediterranean diet.” It is not about eliminating red meat from the diet but about making more moderate use of a product that for millennia was very scarce and now takes up too much space in diets that should be more diverse.
