A new study reveals that consuming more ultraprocessed foods is linked to a higher risk of cognitive decline and stroke, even when following diets such as the Mediterranean, DASH, or MIND diets. These diets, which emphasize plant-based eating, focus on fruits, vegetables, whole grains, beans, and seeds, while limiting sugar, red meat, and ultraprocessed foods.
“If you increased your ultraprocessed food intake by 10% in the study, it increased your risk of cognitive impairment by 16%,” said Dr. Andrew Freeman, director of cardiovascular prevention and wellness at National Jewish Health in Denver, who was not involved in the study. He added, “You can always extrapolate and say, ‘Well, if someone increases their ultraprocessed food consumption by 100%, then they have 160% chance of cognitive impairment.’ Of course, this study can only show an association, not a direct cause and effect.”
On the positive side, the study published in the journal Neurology found that eating more unprocessed or minimally processed foods was linked to a 12% lower risk of cognitive impairment. Unprocessed foods include fresh fruits and vegetables, eggs, and milk, while minimally processed foods are those that include culinary ingredients like salt, herbs, oils, and foods like canned goods and frozen vegetables that are combined with unprocessed foods.
Ultraprocessed foods, including prepackaged soups, sauces, frozen pizza, ready-to-eat meals, and snacks such as hot dogs, sausages, French fries, sodas, cookies, cakes, candies, doughnuts, and ice cream, are typically high in calories, added sugars, and salt, but low in fiber. These nutritional imbalances contribute to cardiometabolic health problems, weight gain, obesity, type 2 diabetes, and high blood pressure.
The study analyzed data from 30,000 participants in the REGARD (REasons for Geographic and Racial Differences in Stroke) study, which includes a diverse group of individuals tracked for up to 20 years. The findings showed that the risk of stroke increased by 8% for those who consumed the most ultraprocessed foods compared to those who ate minimally processed foods, according to study author Dr. W. Taylor Kimberly, chief of the division of neurocritical care at Massachusetts General Hospital in Boston. This risk rose to 15% for Black participants, likely due to the impact of ultraprocessed foods on high blood pressure within this population. Conversely, eating more unprocessed or minimally processed foods was associated with a 9% reduction in stroke risk.
Experts suggest that the detrimental effects of ultraprocessed foods may be due to their poor nutrient composition and tendency to spike blood sugars, leading to conditions such as type 2 diabetes, obesity, elevated blood pressure, and high cholesterol. These conditions are key risk factors for vascular disease in the heart and brain. Additionally, additives such as emulsifiers, colorants, sweeteners, and nitrates/nitrites found in ultraprocessed foods may disrupt the gut microbial ecosystem and cause inflammation, further contributing to stroke and cognitive decline.
The growing body of research on the dangers of ultraprocessed foods is alarming. A February review of 45 meta-analyses involving nearly 10 million people found that a 10% increase in ultraprocessed food consumption raised the risk of developing or dying from dozens of adverse health conditions. The review showed strong evidence that higher intake of ultraprocessed foods was linked to a 50% higher risk of death related to cardiovascular disease and common mental disorders. Additionally, the review found that eating more ultraprocessed foods increased the risk of obesity by 55%, sleep disorders by 41%, type 2 diabetes by 40%, and depression by 20%.
“We really need to put a sign in the ultraprocessed food section, or on the packaging like they do on cigarettes, saying, ‘Warning, this food may be detrimental to your health,’” Freeman said. He emphasized the need to redefine convenience food, suggesting that healthy, shelf-stable options like apples or carrots should be more accessible, particularly to children and in food deserts where ultraprocessed foods often dominate.
As research continues to highlight the health risks associated with ultraprocessed foods, public health strategies and consumer choices must adapt to promote healthier eating habits and reduce the prevalence of diet-related diseases.