A new long-term study published in Neurology has found a concerning link between heavy consumption of ultraprocessed foods and early symptoms associated with Parkinson’s disease — a progressive neurological disorder that affects nearly 1 million Americans.
Researchers analyzed the health data of nearly 43,000 U.S. health professionals over a 26-year period and found that those who consumed 11 or more servings of ultraprocessed foods per day were more than twice as likely to develop three or more early, nonmotor signs of Parkinson’s disease compared to those with the lowest intake. These signs include REM sleep disturbances, depression, pain, and loss of smell.
The findings, which build on broader concerns about ultraprocessed food and brain health, were published May 7 and are now prompting fresh warnings about the long-term effects of industrialized diets.
These results stem from the Nurses’ Health Study and the Health Professionals Follow-Up Study — two large-scale investigations that tracked participants over decades using food diaries and health screenings.
Ultraprocessed foods — including soft drinks, hot dogs, packaged snacks, sweetened yogurts, and condiments like ketchup — are made from components extracted from whole foods, such as starches, oils, and sugars. They are often high in sodium and saturated fats and contain additives that enhance taste and shelf life.
Dr. Xiang Gao, senior researcher and dean at Fudan University’s Institute of Nutrition, noted that participants in the highest intake group had a 2.5-fold greater likelihood of experiencing multiple early Parkinson’s symptoms. This connection was especially pronounced for REM sleep behavior disorder, pain, and depressive symptoms, though not all symptoms were linked equally.
Gao said, “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.” He added that “choosing to eat fewer processed foods and more whole, nutritious foods could be a good strategy for maintaining brain health.”
These findings underscore growing concerns around brain-damaging inflammation caused by poor nutrition and food additives — a risk that extends beyond metabolic disease and into neurological territory.
Editorials accompanying the study echoed the warning. “Excessive ultraprocessed food consumption not only is a risk factor for metabolic diseases but may also accelerate neurodegenerative processes,” wrote Drs. Maria Maraki and Nikolaos Scarmeas of the University of Athens.
Other experts cautioned that while the study shows a strong association, it does not establish a direct cause-and-effect relationship.
Dr. Daniel van Wamelen of King’s College London, who was not involved in the study, noted that a longer follow-up is needed to confirm how many participants eventually develop full Parkinson’s.
Nonetheless, the message is clear: dietary choices today could shape long-term neurological outcomes. With Parkinson’s rates on the rise and no known cure, many researchers believe prevention efforts should begin at the dinner table.