The first large-scale study of the link between diet and dementia finds that what we eat does in fact affect our dementia risk.
In recent years, scientists continue to reinforce the idea that lifestyle choices are major influences on our future brain health. One of the biggest factors of our lifestyle that we can control is our diet. Researchers have found that a Mediterranean diet (fish, olive oil and vegetables), eating flavonoid-enriched foods (fruits, vegetables, tea and wine) and a ketogenic (low-carb) diet like the Keto Diet may boost brain health; while other diets enriched with saturated fats like pastries, butter and fried foods have been found to have links to higher Alzheimer’s and dementia risk. Now, there is an addition to the diet cons list: processed meats.
Our global population relies heavily on processed foods — bacon, sausage, ham — which all notably cause high cholesterol and hypertension, common comorbidities of cognitive decline.
Although diet is a choice, the expansive nature of food deserts (when fresh food or supermarkets are not within convenient traveling distances) across the globe lock people into unhealthy eating habits. As of 2009 in the United States alone, roughly 23 million people live in food deserts, according to the U.S. Department of Agriculture.
In a recent study published in the American Journal of Clinical Nutrition, and the first-large scale study of its kind, scientists found that a 25-gram serving of processed meat a day correlates to a 44-percent increased risk in developing dementia.
But, if you have been eating processed meats don’t fret just yet, as researchers also found that eating unprocessed red meat (beef, pork or veal) could be protective of your brain health — those who consumed 50g a day were 19 percent less likely to develop dementia.
Lead researcher of the study Huifeng Zhang says the prevalence of dementia is increasing worldwide, and our diet may play a bigger role than previously thought. “Our research adds to the growing body of evidence linking processed meat consumption to increased risk of a range of non-transmissible diseases,” Zhang said in a press release.
500,000 people from the UK aged 40 to 69 were involved in the study, as dementia is the UK’s leading cause of death, with America clocking Alzheimer’s at number six. The data collected from the participants between 2006 and 2010 focused on six different meat options, where participants would choose whether they never ate it, or ate it once or multiple times a day. 2,896 participants were diagnosed with dementia over an eight-year average after the study was conducted.
This is just over half a percent of the total study participants, leaving some scientists to suggest that the data does not make a very strong case. Professor Robert Howard, an expert in ageing at University College London describes the data as something that “wouldn’t persuade me to give up my breakfast bacon.”
Among this small 0.57 percent of participants who did develop dementia, this pool tended to be older, more economically deprived, less educated, more likely to smoke, less physically active, more likely to have strokes and dementia diagnoses in their family history, and were more likely to be carriers of APOE4, a gene highly associated with the causation of dementia and Alzheimer’s. Overall, more men than women were diagnosed with the disease in the participant pool.
While some people in the study were three to six times more likely to develop dementia due to the ApoE4 gene, which increases risk of Alzheimer’s, the researchers say that the findings of the study still correlate eating processed meat with dementia risk aside from any genetic predisposition.
The study also suggests that people who consume higher amounts of processed meats are more likely to be male, as well as to have several other risk factors that have been linked to dementia, including being less educated, smoking, being overweight or obese, having lower intakes of vegetables and fruits, and having higher intakes of protein and fats, including saturated fat.
Meanwhile, the findings uphold earlier research from in 2018 that indicated eating plant-based foods, whole grains, beans, nuts, vegetable oils and fish, can curb cognitive decline.
The Mediterranean diet, adjusted in this study for American eating habits, appeared to reduce Alzheimer’s risk by just over a third. The researchers said that is because the nutrients found in this diet assist in fighting off otherwise damaging inflammation and oxidation in the brain.
“Further confirmation is needed, but the direction of effect is linked to current healthy eating guidelines suggesting lower intakes of unprocessed red meat could be beneficial for health,” Zhang said.
Professor Janet Cade, who provided oversight during the study, believes that any exploration of dementia risk factors is the only way to try and reduce the growing rates of people who are diagnosed with dementia. She noted, “This analysis is a first step towards understanding whether what we eat could influence that risk.”
UPDATE, March 1, 2023, 12:01 a.m. – This article from April 16, 2021 was updated with new information for our readers.