• Posted May 8, 2025

Ultra-Processed Foods Linked To Parkinson's Disease Risk

Fast food and ready-made packaged eats could be doing slow damage to people’s brains.

Ultra-processed foods like breakfast cereals, soft drinks, hot dogs and ketchup appear to increase a person’s risk of developing Parkinson’s disease, a new study says.

People who ate about 11 servings of ultra-processed foods per day had a 2.5-times higher risk of developing three or more early symptoms of Parkinson’s than those who ate the least amount, researchers reported May 7 in the journal Neurology.

Single-serving examples of ultra-processed foods include a can of soda, an ounce of potato chips, a slice of packaged cake, a single hot dog or a tablespoon of ketchup, researchers said.

“Eating a healthy diet is crucial as it has been associated with a lower risk of neurodegenerative diseases and the dietary choices we make today can significantly influence our brain health in the future,” senior researcher Dr. Xiang Gao, dean of the Fudan University Institute of Nutrition in Shanghai, said in a news release.

“There's growing evidence that diet might influence the development of Parkinson's disease,” Gao continued. “Our research shows that eating too much processed food, like sugary sodas and packaged snacks, might be speeding up early signs of Parkinson's disease.”

Parkinson’s disease is a progressive movement disorder that causes people to shake, become stiff or have trouble with their balance and coordination. It occurs when the brain cells that create the hormone dopamine die or become impaired, according to the National Institute on Aging.

Ultra-processed foods are made mostly from substances extracted from whole foods, like saturated fats, starches and added sugars. They also contain a wide variety of additives to make them more tasty, attractive and shelf-stable, including colors, emulsifiers, flavors and stabilizers.

For this study, researchers tracked the health of nearly 43,000 U.S. health professionals participating in two ongoing large-scale medical studies.

None had Parkinson’s at the start of the study. With an average age of 48, they were followed for up to 26 years with regular medical exams, health questionnaires and food diaries.

The research team looked for early symptoms of Parkinson’s among the participants, including problems with rapid eye movement (REM) sleep, constipation, depression, body pain, impaired color vision, excessive daytime sleepiness and reduced ability to smell.

They then compared those symptoms to people’s intake of ultra-processed foods, after dividing the participants into five groups based on how much manufactured eats they consumed.

People in the highest-intake group — 11 or more servings a day — had a 2.5-fold greater risk of three or more early signs of Parkinson’s compared to those in the lowest-intake group with fewer than three daily servings.

Eating more ultra-processed foods was linked to increased risk of nearly all early Parkinson’s symptoms except constipation, researchers added.

Ultra-processed foods tend to contain high levels of unhealthy nutrients like excess sugar, sodium and saturated fats, which might explain their link to Parkinson’s, researchers said. Food additives also might contribute to brain-damaging inflammation.

“Choosing to eat fewer processed foods and more whole, nutritious foods could be a good strategy for maintaining brain health,” Gao said. “More studies are needed to confirm our finding that eating less processed food may slow down the earliest signs of Parkinson's disease.”

More information

The Michael J. Fox Foundation for Parkinson’s Research has more on Parkinson’s disease.

SOURCE: American Academy of Neurology, news release, May 8, 2025