Love bacon? Just one slice is all it takes to raise your risk of dementia

BOSTON — If you could see inside your brain after eating processed meats, you might think twice about that morning bacon ritual. An eye-opening new study has revealed that even modest consumption of processed red meat could be aging your brain faster than normal.

Doctors from Brigham and Women’s Hospital and the Harvard T.H. Chan School of Public Health followed over 133,000 healthcare professionals for up to 43 years, finding that people who ate just a quarter serving or more of processed red meat per day had a 13% higher risk of developing dementia compared to those who consumed minimal amounts. For perspective, a serving of red meat is about three ounces – roughly the size of a deck of cards.

Most previous studies exploring the connection between red meat consumption and brain health have been relatively small or short-term, making this extensive research particularly noteworthy. The study, published in Neurology, carefully defined its terms: processed red meat included products like bacon, hot dogs, sausages, salami and bologna, while unprocessed red meat encompassed beef, pork, lamb and hamburger.

While both types of red meat have been previously linked to conditions like Type 2 diabetes and cardiovascular disease, processed meats carry additional risks due to their high levels of sodium, nitrites, and other potentially harmful compounds. These substances can trigger inflammation, oxidative stress, and vascular problems that may contribute to cognitive decline.

Participants were divided into three consumption groups for processed meat: those eating fewer than 0.10 servings per day (low), between 0.10 and 0.24 servings daily (medium), and 0.25 or more servings per day (high).

Beyond just tracking dementia diagnoses, researchers also assessed participants’ cognitive function through telephone interviews and questionnaires. Those who regularly consumed processed red meat showed signs of accelerated brain aging – approximately 1.6 years of additional cognitive aging for each daily serving. In practical terms, this means their brain function declined as if they were over a year and a half older than their actual age.

To assess cognitive decline from multiple angles, the researchers examined both subjective and objective measures. A group of nearly 44,000 participants with an average age of 78 completed surveys rating their own memory and thinking skills. This self-reported assessment revealed that those consuming 0.25 or more servings of processed meat daily had a 14% higher risk of subjective cognitive decline compared to minimal consumers.

Intriguingly, the study found that replacing processed red meat with healthier protein sources could help protect brain health. Swapping out that daily serving of bacon or hot dogs for nuts and legumes was associated with a 19% lower risk of dementia. Fish proved even more beneficial, with a 28% reduction in dementia risk when substituted for processed meat.

The research team focused on two large cohorts of health professionals: the Nurses’ Health Study and the Health Professionals Follow-Up Study. These groups were ideal for long-term research as they were already completing detailed dietary questionnaires every 2-4 years and had high rates of follow-up participation. The participants’ professional backgrounds also meant they were likely to provide accurate health information.

Women made up about two-thirds of the study population, with an average starting age of 49 years. By following participants for several decades, researchers could observe how dietary patterns in middle age influenced cognitive health later in life. This long-term perspective is crucial, as cognitive decline often begins subtly, years before noticeable symptoms appear.

“Dietary guidelines tend to focus on reducing risks of chronic conditions like heart disease and diabetes, while cognitive health is less frequently discussed, despite being linked to these diseases,” said corresponding author Dr. Daniel Wang, of the Channing Division of Network Medicine at Brigham and Women’s Hospital, in a statement. “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.”

Having that hot dog at the baseball game or bacon at Sunday brunch are certainly delicious traditions in the American diet. With dementia rates expected to soar in the next 30 years, it seems that developing the devastating condition could eventually be a tradition too. Taking the right steps to protect your brain can rewrite that fate.