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  • More than 70% of the food supply in the U.S. consists of ultra-processed foods.
  • A recent study linked eating ultra-processed foods to an increased risk for 32 adverse health conditions.
  • A new study from researchers at Massachusetts General Hospital in Boston says consuming ultra-processed foods may also increase a person’s risk for stroke and cognitive decline.

More than 70% of the food supply in the United States consists of ultra-processed foods — foods that are industrially made and generally contain high amounts of fats, sugars, and salt.

Past studies show that we are eating more ultra-processed foods than ever before, with people in the U.S. and the United Kingdom getting more than 50% of their daily energy intake from these types of foods.

A recent study linked eating ultra-processed foods to an increased risk for 32 adverse health conditions, including heart disease, mental health issues, type 2 diabetes, respiratory problems, poor sleep, and cancer.

Now, a new study published this week from researchers at Massachusetts General Hospital in Boston says consuming ultra-processed foods may also increase a person’s risk for stroke and cognitive decline.

For this study, researchers recruited more than 30,000 Black and white study participants ages 45 or older to see how eating ultra-processed foods affected their brain health.

“When thinking about preserving and maintaining brain function throughout our life it’s important to identify factors that we can change — in other words, modifiable risk factors — that can alter that risk,” W. Taylor Kimberly, MD, PhD, Chief of the Division of Neurocritical Care and a neurologist in the Department of Neurology at Massachusetts General Hospital in Boston and senior author of this study told Medical News Today. “Understanding how ultra-processed foods affect the brain can inform a strategy to then reduce that risk.”

For an average of 11 years, study participants filled out questionnaires about what they ate and drank. From that information, scientists determined what percentage of their daily diet included ultra-processed foods.

At the end of the study, Kimberly and his team found that 768 participants were diagnosed with cognitive impairment.

People whose diet included 25.8% of ultra-processed foods developed memory and thinking problems, compared to those who ate 24.6% of ultra-processed foods that did not develop cognitive issues.

After adjusting for certain factors that could increase dementia risk, such as age and gender, researchers found that a 10% increase in the amount of ultra-processed foods consumed was associated with a 16% heightened risk of developing cognitive impairment.

Scientists also reported eating more unprocessed or minimally processed foods was correlated with a 12% lower risk of cognitive issues.

“We know that there are several independent factors that contribute to memory and thinking problems, especially as we age,” Kimberly said. “When someone comes to their doctor with these types of symptoms, it’s important to figure (out) which of these are contributing, and then to intervene against those factors to the extent possible.”

“The goal of our study was to provide further insight into the role of diet, and of ultra-processed foods in particular, on this broader problem of cognitive decline,” he added. “Importantly, our finding of the association between ultra-processed foods and brain health also points towards potential ways to protect our brain function.”

When looking at stroke risk, researchers found that the diets of the 1,108 study participants who had a stroke by the end of the study consumed 25.4% of ultra-processed foods, compared to 25.1% for those who did not have a stroke.

After certain adjustments, scientists discovered that eating more ultra-processed foods was tied to an 8% increased risk of stroke.

They found that people who did not eat as much ultra-processed foods, instead turning to minimally processed foods, had a 9% lower risk of stroke.

Researchers also found that the effect of ultra-processed food consumption on stroke risk was greater among Black participants, with a 15% comparative increase in stroke risk when compared to white participants.

“In a similar manner to the role of ultra-processed foods in cognitive decline, we found an association between ultra-processed foods and future risk of stroke,” Kimberly explained. “For those who are interested in protecting and maintaining their brain function, it would be reasonable to reduce the amount of ultra-processed foods in the diet.”

“As a general rule, if the food cannot be easily made in your own kitchen, it may make sense to reduce that as a part of your diet,” he added. “Even relatively small changes have the potential to have an impact.”

After reviewing this study, José Morales, MD, vascular neurologist and neurointerventional surgeon at Pacific Neuroscience Institute in Santa Monica, CA, told MNT these findings are not surprising, but provide a great tie-in to universally agreed upon primary prevention strategies that promote healthy living and aging to avoid stroke and dementia as we age.

“Unsurprisingly, select minority populations underserved by healthcare are those that bear the greatest risks (of) cognitive impairment/stroke from consuming ultra-high-processed foods, which highlights the efforts the healthcare community should undertake to address healthcare disparities and promote brain health for all irrespective of race or socioeconomic status,” Morales added.

MNT also spoke with Monique Richard, MS, RDN, LDN, a registered dietitian nutritionist and owner of Nutrition-In-Sight, who agreed.

“In clinical practice, on a daily basis, I see the impact and collateral damage of predominantly consuming a diet composed of ultra-processed foods,” Richard explained. “Most foods that are categorized as ultra-processed foods, not all, and the arguments can be nuanced based on the criteria, but, in general, are devoid of quality nutrients, phytochemicals, fiber, and ingredients that support health and vitality.”

“When the human body is not nourished and nurtured with nutrients that support life, cellular health, and biological processes, not only can the system operations themselves be impacted but damage can be compounded with ingredients that can be harmful or counterproductive to cell turnover and processes,” she continued. “The brain is no exception. It is an intricate universe within itself that thrives on healthy fats, proteins, carbohydrates, hydration, activity, and connection — with nature and other humans.”

For readers looking to have less ultra-processed foods in their diet,

Morales said the simple adage “slow food is good and fast food is bad” can be a good guide.

“Preparing one’s own meals with healthy, ‘whole’ ingredients and eating foods that are minimally processed is a great start, but difficult for many accustomed to the conveniences of ‘faster’ foods and those who live in food deserts,” he continued. “Specifically, the foods to avoid would be sugary drinks, fried food, high salt content foods, simple carbohydrates, red meat, and pork. Unprocessed and raw fruits, vegetables, nuts, fish, and moderate intake of white meats should be the types of foods we strive to incorporate to optimize our body and brain health.”

Aside from meeting with a registered dietitian nutritionist to understand what a person specifically needs to optimize their cognitive health and function, Richard recommended readers arm themselves with education and resources and ask themselves:

  • Do I have access and the ability to eat more servings of fruits and vegetables packaged in their own skin, five different ones in a day?
  • Could I cook more meals at home in a day or during the week with the main ingredients being food itself — not filler ingredients, salt, sugar, or preservatives but add my own herbs and spices?
  • Could I add one simple habit on a daily basis to support my brain and heart? Examples may include: eating a handful of walnuts, drinking 60-80 ounces of water instead of diet or regular soft drinks or sweetened tea, getting 10 minutes of fresh air 3 times a day, going for a brisk walk
  • Could I try a new recipe with foods like beans, fish, and “new to me” vegetables