Eating processed red meat may be a significant risk factor for dementia, according to a large study that tracked more than 100,000 people over four decades.
Processed red meat has previously been shown to increase the risk of cancer, heart disease and type 2 diabetes. Now US researchers say they have discovered a potential link with dementia.
The study also found that replacing processed red meat with healthier foods such as nuts, beans or tofu can help reduce the risk of dementia. The findings were presented at the Alzheimer’s Association’s international conference in the US.
The number of people living with dementia worldwide is expected to nearly triple to 153 million by 2050, and studies looking at diet and risk of cognitive decline have become a focus of researchers.
In the latest research, experts studied the health of 130,000 nurses and other health professionals working in the US. They were tracked for 43 years and provided data on their diet every 2 to 5 years.
The participants were asked how often they ate processed red meat, including bacon, hot dogs, sausages, salami and other sandwich meats.
They were also asked about their consumption of nuts and legumes, including peanut butter, peanuts, walnuts and other nuts, string beans, beans, peas, soy milk and tofu.
More than 11,000 cases of dementia were identified during the follow-up period.
Consuming two servings of processed red meat per week appears to increase the risk of cognitive decline by 14% compared to those who eat about three servings per month, the researchers reported.
The study also suggested that substituting one daily serving of processed red meat for a daily serving of nuts, beans or tofu each day could reduce the risk of dementia by 23%.
The study’s lead author, Dr Yuhan Li, an assistant professor at Brigham and Women’s Hospital in Boston, said: “Study results are mixed on whether there is a link 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.
“By studying people over a long period of time, we found that eating processed red meat may be a significant risk factor for dementia.”
Li, who conducted the study while at the Harvard TH Chan School of Public Health in Boston, added: “Dietary guidelines may include recommendations that limit them to promote brain health.
“Processed red meat has also been shown to increase the risk of cancer, heart disease and diabetes. It can affect the brain because it has high levels of harmful substances such as nitrites [preservatives] and sodium.”
Dr Heather Snyder, from the Alzheimer’s Association, said: “Prevention of Alzheimer’s disease and all other dementias is a major focus, and the Alzheimer’s Association has long encouraged eating a healthier diet – including foods that are less has been processed – because it is associated. with lower risk of cognitive decline. This large long-term study provides a specific example of one way to eat healthier.”
Dr Richard Oakley, of the Alzheimer’s Society UK, said: “In this study, more people who ate processed red meat developed dementia and had worse memory and thinking skills.”
However, he urged caution because the research only found a link between processed red meat and dementia – and did not prove cause and effect.
“It is important to remember that this does not mean that eating processed red meat is directly related to the development of dementia. It may be that people who avoid processed red meat are generally more health conscious and avoid other unhealthy habits that increase dementia risk.”
