The Link Between Processed Foods and Parkinson's
An extensive American study has found that daily consumption of ultra-processed foods—such as snacks, hot dogs, sugary drinks, and packaged pastries—may double the risk of developing early neurological symptoms linked to Parkinson’s disease.
Dr. Meir Kestenbaum of Meir Medical Center explains: “According to the study, people who consumed less processed food—up to three servings a day—were significantly less likely to develop the symptoms we associate with the prodromal stage of Parkinson’s.”
Snacks, Sugary Drinks, and Packaged
Pastries—A Neurological Warning Sign?
Daily consumption of ultra-processed food might increase the risk of
early Parkinson’s-related symptoms, according to a large-scale study
published this week in Neurology. The findings, based on nearly 20 years
of dietary and health tracking for tens of thousands of participants,
point to a clear link between diets high in ultra-processed foods and
the early emergence of neurological signs—well before any formal
diagnosis.
“Participants reported their eating habits
for over two decades, and researchers then checked whether they
developed symptoms that could be related to Parkinson’s,” explains Dr.
Meir Kestenbaum, Deputy Head of Neurology and Director of the Movement
Disorders Clinic at Meir Medical Center. “The foods in question were
primarily snacks, sweets, sugary drinks, and junk food—what we define as
ultra-processed foods.”
Hot Dog, Bun, and a Risk to Your Brain
The study analyzed dietary data from nearly 43,000 participants drawn
from two long-term U.S. studies: the Nurses’ Health Study and the Health
Professionals Follow-Up Study, both ongoing for over 30 years. None of
the participants had Parkinson’s at the start, and their average age was
48. Every few years, they were asked to report their dietary habits—a
potential limitation, as self-reports aren’t always reliable.
One serving of ultra-processed food was defined in the study as 240 ml
of soda (diet or regular), a single hot dog, a slice of packaged cake, a
tablespoon of ketchup, or about 28 grams of chips—less than a standard
bag. White bread or processed-grain buns were also counted as separate
servings.
According to Dr. Kestenbaum, “People who ate fewer than three servings
of processed food per day were significantly less likely to develop the
non-motor symptoms we associate with Parkinson’s prodrome. In contrast,
those who consumed around 11 servings a day had a 2.5 times higher risk
of early Parkinson’s symptoms.”
Not Parkinson’s Yet—but Maybe On the Way
The study focused on the "prodromal stage"—a period when non-motor
symptoms start appearing, sometimes decades before the disease is
officially diagnosed. These symptoms can include body aches,
constipation, low mood, daytime drowsiness, changes in the sense of
smell or color perception, and a rare REM sleep disorder where people
physically act out their dreams.
“We now understand that such early symptoms
may appear many years before hallmark motor issues like tremors,
stiffness, slow walking, or instability,” says Dr. Kestenbaum. “And
while we don’t have conclusive proof that these early signs always lead
to Parkinson’s, it’s clear that this group is at increased risk.”
At the same time, researchers emphasize that no direct link was found
between ultra-processed food consumption and an official Parkinson’s
diagnosis. “The study didn’t examine whether participants were later
diagnosed with the disease,” said Dr. Daniel van Wamelen of King’s
College London, who was not involved in the research. “However, a high
occurrence of early symptoms does indicate a higher risk down the line.
Less Fiber, More Inflammation
The researchers offered several biological explanations for the possible
harm of ultra-processed food: low fiber content, lack of protein and
essential micronutrients, and excess sugar, salt, saturated fats, and
trans fats. Artificial additives may also disrupt gut bacteria balance,
promote inflammation, and generate free radicals—all known to harm nerve
cells.
“There’s no definitive proof that processed
food itself causes these symptoms,” Dr. Kestenbaum clarifies. “It might
be an indirect effect via the digestive system or due to external
toxins that damage nerve cells. There are still many unanswered
questions, but it’s clearly a significant research direction—especially
since we currently have no proven treatment to prevent Parkinson’s.”
He closes with a cautious but hopeful message: “We already know that
processed food is linked to diabetes, obesity, high cholesterol, and
heart disease. Now it seems it could also be tied to neurodegenerative
conditions. The jury is still out, but it’s a path worth following.”
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