Parkinson's disease (PD) is a well-known neurodegenerative disorder, the second most common behind Alzheimer's, affecting roughly 10 million people worldwide. While it doesn’t currently have a cure, several types of treatment exist. Are probiotics for Parkinson's patients effective? Research is promising.
In recent years, researchers have begun to better understand the microbiota-gut-brain axis, the bidirectional influence between intestinal microbes and the brain. Although much research needs to be done to understand more details of this communication pathway, emerging research in probiotics suggests that people with PD may benefit from a gut-brain probiotic.
Probiotics, which are live microbes that produce a health benefit in adequate amounts, can help people with certain diseases such as Parkinson’s. Researchers continue to study which probiotic strains are more beneficial for PD patients. Psychobiotics are the types of probiotics that may benefit mental health or neurological conditions such as PD.
Before we dive into the potential benefits of probiotics for PD patients, let’s take a closer look at Parkinson's disease, as well as the science behind probiotics and what role the gut-brain axis plays. You'll learn how probiotics may help you, and about the exciting research behind PS128. PS128 is the clinically researched probiotic strain in Neuralli MP, a unique probiotic medical food for Parkinson’s patients.
What is Parkinson's disease?
Parkinson's disease is a progressive movement disorder that worsens over time. Most commonly, patients develop PD symptoms after age 60. However, some people develop tremors and other symptoms much earlier. So-called “young-onset” or “early-onset” Parkinson's disease” (YOPD or EOPD), affects roughly 10-20% of those who are diagnosed.
PD patients experience cell loss in the region of the brain known as the substantia nigra. This region of the brain creates dopamine, a neurotransmitter that helps control movements in the body. Low dopamine levels cause the patient to lose regulation of their movement. Patients typically only begin to experience tremors and other typical motor symptoms after about 50% of the cells have been damaged or lost.
In a Parkinson's disease brain, the protein alpha-synuclein clumps up into aggregates called Lewy bodies. Researchers believe that this aggregation within the substantia nigra may be a cause of PD.
What causes PD?
As neurons in the substantia nigra die, dopamine levels decrease, leading to PD development. Although we know that the loss of dopamine-producing neurons causes PD, there's still debate over what causes these neurons to die in the first place.
The build-up of alpha-synuclein aggregates in neurons may be a factor. However, other factors that contribute to neuronal death may cause alpha-synuclein aggregation or act independently of it.
Some studies have pointed to genetics. Variations in over a dozen different genes correlate with an increased risk of developing Parkinson's disease. In fact, genetic factors are estimated to contribute approximately 25% to the overall risk of developing PD. However, not everyone with these genetic variations develops the disease.
Another inconclusive theory points to environmental factors as contributors – specifically pesticides and herbicides, as well as traffic and industrial pollution. It’s likely that for many PD patients, a variety of risk factors are involved.
Gut health and Parkinson's disease
Many PD patients experience gastrointestinal problems years before developing motor symptoms, which has prompted researchers to look into a gut-brain connection for the cause of PD. In these “gut-first” patients, alpha-synuclein begins to aggregate in the gut's enteric nervous system (ENS) and spreads to the brain.
In these studies, researchers pointed to alpha-synuclein as a primary contributor to PD. These studies show that in some patients, alpha-synuclein originated in the ENS in the gut and later affected the central nervous system (CNS).
These “gut-first” patients also were at high risk of REM sleep behavior disorder (RBD) and other autonomic system symptoms prior to developing symptoms associated with decreased dopamine.
However, not all patients have this “gut-first” accumulation of alpha-synuclein, which is why separate subtypes of gut-first and brain-first PD exist.
Can probiotics help PD patients?
Given probiotics’ ability to affect the gut, and the gut-brain axis’s role in PD, could there be essential microbes that a Parkinson’s patient needs in their diet?
Food provides nutrients that are necessary for many functions in the body, including the production of neurotransmitters such as dopamine. Emerging research on the gut-brain axis suggests that some probiotics can impact the brain by influencing the signaling from the gut microbiome to the brain.
The microbial community in the gut is significant, containing bacteria, yeast, viruses, and protozoa. These gut microbiota digest food, synthesize vitamins, and help us maintain a healthy barrier between what’s inside our gut and intestinal cells. The skin, mouth, vagina, and other organs also have their own microbial inhabitants that help maintain good overall health and wellness.
The microbiome contains both good and bad bacteria. Overgrowth of "bad" forms of bacteria can cause poor gut health. This is called gut dysbiosis.
Sometimes simply adding prebiotic foods to the diet can support the growth of “good” bacteria in your gut microbiota. Other times, you might want a probiotic that has shown specific benefits for gut health to achieve health benefits beyond what can be found in foods.
Although live cultures can be found in many fermented foods, taking a probiotic with demonstrated clinical effects at specific amounts will be much more impactful.
Probiotics and probiotic medical foods are typically packaged in the form of a pill, capsule, drink, or powder. Gut health probiotics are a great option if your diet isn’t holistic or you want to take extra measures for your overall wellness.
Different probiotic strains can have different benefits, so it’s important to be aware of all the options to ensure you choose the right strain for your needs.
A Parkinson's probiotic medical food that provides the missing microbes needed for signaling from the gut to the brain could result in meaningful differences in their quality of life.
Because not all probiotics are the same, a PD patient, with the supervision of a health care practitioner, could consider a probiotic that has been tested in PD and shown to produce benefits.
Best neurological health probiotics for PD
The gut and brain can influence each other through the gut-brain axis. Certain probiotics may be able to influence this communication pathway. Psychobiotics, for example, might influence the activity of neurotransmitters in the brain as one way of impacting mental or neurological conditions.
In the case of PD, a psychobiotic strain that can adjust brain dopamine levels may provide dietary management of your condition.
A handful of animal studies have suggested that certain probiotics with anti-oxidant effects can be neuroprotective, and improve movement in animal models of Parkinson’s (here is one example).
Interestingly, L. plantarum PS128, as of this writing, is likely the first of two documented probiotic strains (the other being PS23) known to increase dopamine activity in the brain, which is a critical factor in PD. Two studies (here and here), have shown that mice taking PS128 have higher dopamine levels in their brains compared to the mice that did not take the probiotic.
A pilot single-arm study suggests that PS128 may send signals to the brain to affect neurological activity in a way that is relevant to Parkinson’s patients. Twenty-five patients who were taking levodopa and had had Parkinson’s for an average of 10 years took two capsules of PS128 per day for 12 weeks.
At the end of the study, participant's motor scores indicated a significant improvement in motor function. The majority of participants also said they received a noticeable benefit from PS128.
Aspects of quality of life such as mobility and improved ability to perform daily activity improved. Additionally, the participants reported longer ON periods, meaning the medication was working for a longer period of time, and shorter OFF periods.
PS128 is available commercially as a probiotic medical food called Neuralli MP.
Best gut health probiotics for Parkinson's disease
While nearly three out of every four PD patients experience constipation, PD patients also may experience other gastrointestinal symptoms such as feeling a sense of fullness after eating very little (gastroparesis) or difficulty swallowing (dysphagia) at almost the same prevalence. This could be because of a degeneration of the vagus nerve, lack of enteric dopamine, or a side effect of typical PD meds.
Two common low-cost remedies for constipation are a diet low in protein/sugar and high in fiber, and stimulant laxatives like polyethylene glycol. Abdominal massage can also be helpful in stimulating movement of the intestinal contents. Increasing dietary fiber intake is also associated with greater stool frequency for those struggling with constipation.
Strategies for managing the slow rate of emptying from the stomach (gastroparesis) may include addressing any nutrient deficiencies or a low-fiber or low-fat diet with liquids and protein supplements. Unfortunately, a low-fiber diet may be difficult if someone is experiencing both gastroparesis and constipation.
Approaches to difficulty swallowing may include lifestyle changes like more chewing, smaller amounts of food at one time, or softer foods. If more help is needed, swallowing therapy is an option to try before turning to more invasive treatments.
Probiotics offer an easy and low-risk option for dealing with gut issues such as constipation. They may even do more than just help you move your bowels.
Studies suggest that gut dysbiosis may lead to an overactive immune response, which can trigger a chain reaction of undesirable effects. These effects include a weakened intestinal barrier and reduced short-chain fatty acids, which have been demonstrated in cases of PD. Balancing the gut microbiome with beneficial bacteria from a probiotic may help with some or all of these issues.
Some studied probiotics have been accepted as safe and effective for PD-associated GI problems, including constipation, by the International Parkinson and Movement Disorder Society Evidence-Based Medicine Committee.
Additionally, a recent meta-analysis of probiotic trials demonstrates evidence for some probiotics to be well-tolerated and beneficial for constipation. While human clinical trials and studies are ongoing, certain Lactobacillus and Bifidobacterium strains have shown positive results for constipation in PD patients, with some even featured by the American Parkinson Disease Association.
The hopeful connection between probiotics & Parkinson’s disease
In the past, Parkinson's disease was recognized as a neurological disorder that was caused by and affected the brain. However, many researchers and physicians are beginning to point to a clear connection between the gut microbiome and PD. This has led researchers to wonder if getting ahead of gut health could not only help manage GI difficulties but also possibly slow neurodegeneration processes that start in the gut.
Gut-brain psychobiotics like PS128 may be a useful support for gut microbiome-to-brain signaling in Parkinson's. The clinically-researched PS128 strain is present in Neuralli MP, a probiotic medical food for the dietary management of ASD and PD. More research is needed to further understand the way this unique probiotic impacts the brain, but the results of clinical studies are encouraging.
If you or a loved one have PD, consider trying Neuralli MP.
(Updated September 17, 2025)
Recommended reading:
PS128 Probiotic & Parkinson’s - How Does it Work?
