Could Ultra-Processed Foods Increase the Risk of Parkinson’s Disease?

The foods you choose every day may affect more than your waistline or heart health. Growing evidence suggests that diets high in ultra-processed foods may also have long-term effects on brain health, including a possible increased risk of Parkinson’s disease.

Although researchers have not proven that ultra-processed foods directly cause Parkinson’s disease, recent studies have found a concerning association between high consumption of these foods and early signs of the neurological disorder. The findings add to the growing list of reasons to emphasize whole, minimally processed foods as part of a healthy lifestyle, explains Samer D. Tabbal, M.D., a neurologist and director of the Movement Disorders Program and Endowed Chair in Movement Disorders at Baptist Health Miami Neuroscience Institute.

"Could the food that you eat today predict your risk of Parkinson's disease in the long run?" Dr. Tabbal asks in a recent Baptist Health Instagram reel. "It looks like people who eat a lot of ultra-processed foods are at a higher risk of having Parkinson's disease."

What Are Ultra-Processed Foods?

Ultra-processed foods are industrially manufactured products that contain ingredients rarely used in home cooking. They often include preservatives, artificial flavors, colors, emulsifiers, sweeteners and other additives designed to improve shelf life, texture or taste.

Examples include:

• Sugary breakfast cereals
• Packaged cookies and cakes
• Chips and snack foods
• Hot dogs and processed meats
• Instant noodles
• Frozen ready-to-eat meals
• Soft drinks and many energy drinks

"Ultra-processed foods are foods that contain a lot of additives, mainly chemicals, that the industry adds to the food to make it last longer," said Dr. Tabbal.

While many processed foods can be part of a balanced diet, nutrition experts generally recommend limiting ultra-processed foods because they often contain high amounts of added sugar, sodium and unhealthy fats while providing relatively little fiber and essential nutrients.

Understanding Parkinson's Disease

Parkinson's disease is a progressive neurological disorder that affects movement. It develops when nerve cells in an area of the brain gradually die or become damaged. These cells normally produce dopamine, a chemical messenger that helps coordinate smooth, controlled movement.

As dopamine levels decline, people may develop symptoms such as:

• Tremor, often beginning in one hand
• Slowed movement
• Muscle stiffness
• Balance problems
• Changes in walking
• Reduced facial expression

Many people also experience non-motor symptoms, including constipation, reduced sense of smell, sleep disorders, anxiety and depression, years before movement symptoms appear.

Although aging remains the greatest risk factor, scientists believe Parkinson's disease develops from a combination of genetic susceptibility and environmental exposures.

New Research Points to a Possible Link

One of the largest studies examining diet and Parkinson's disease was published in Neurology in 2025.

Researchers analyzed dietary information collected over decades from more than 42,000 healthcare professionals who did not have Parkinson's disease at the beginning of the study. They found that participants who consumed the highest amounts of ultra-processed foods were significantly more likely to develop multiple prodromal features of Parkinson's disease. "Prodromal" refers to early warning signs that can appear years before the classic movement symptoms develop.

The researchers emphasized that the study found an association, not proof that ultra-processed foods cause Parkinson's disease. Other lifestyle factors could also contribute to the increased risk.

Still, the findings support previous research linking ultra-processed foods to dementia, cardiovascular disease, obesity and other chronic illnesses.

Why Might Ultra-Processed Foods Affect the Brain?

Scientists are still investigating the biological mechanisms behind the association.

Several theories include:

Inflammation. Diets high in ultra-processed foods may promote chronic inflammation throughout the body, including the brain.

Oxidative stress. This refers to damage caused when harmful molecules called free radicals overwhelm the body's natural defenses. Oxidative stress has long been implicated in Parkinson's disease.

Gut health. Increasing evidence suggests that changes in the gut microbiome—the trillions of bacteria living in the digestive tract—may influence brain health. Some researchers believe Parkinson's disease may even begin in the gut before affecting the brain.

Chemical exposures. Food additives and contaminants remain an active area of research.

"We know from many studies in the past that chemicals are not good for your brain,” Dr. Tabbal notes. “They are associated with dementia, and they may also be associated with cancers."

Although scientists have not identified specific food additives as direct causes of Parkinson's disease, many experts agree that limiting unnecessary exposure to potentially harmful chemicals is a reasonable preventive strategy.

The Role of Environmental Toxins

Diet is only one possible piece of a much larger puzzle.

Researchers have long linked certain environmental exposures—including some pesticides, industrial solvents and heavy metals—to an increased risk of Parkinson's disease.

Dr. Tabbal believes these broader environmental influences deserve attention.

"The Greeks and the Egyptians at the times of the Pharaohs never described Parkinson's disease," he says. "Now, you may think, well, people did not live long enough to have Parkinson's disease back then, but we know for a fact that there are people who have Parkinson's disease at a very early age. The risk of Parkinson's disease is very likely related to chemicals and toxins in the environment."

While historical comparisons cannot prove cause and effect, modern researchers increasingly recognize that environmental factors likely interact with genetics over many years to influence disease risk.

A Brain-Healthy Eating Pattern

Rather than focusing on eliminating a single food, experts recommend adopting an overall dietary pattern that supports long-term brain health.

Dr. Tabbal offers straightforward advice. "So, ultra-processed foods are bad for you. Too much sugar is bad. Too much chemicals are bad. Too much additives are bad."

Instead, he recommends choosing foods closer to their natural state.

"Your best bet is to eat whole grains, fresh foods, fruits and vegetables, and a high-fiber diet,” Dr. Tabbal stresses. “There's a lot of way to improve the health of your brain, and not eating artificial food is one of them."

A high-fiber diet includes foods such as beans, lentils, oats, whole grains, vegetables and fruits. Fiber supports digestive health and helps nourish beneficial gut bacteria that may influence inflammation and brain function.

Many neurologists also recommend dietary patterns such as the Mediterranean diet, which emphasizes vegetables, fruits, whole grains, legumes, nuts, fish and olive oil, while limiting highly processed foods.