The Power in the Plate: How a New Diet Score Offers Hope for Slowing Parkinson’s Progression

Dr. Lori Mishley, a Doctor of Naturopathic Medicine and PhD in Nutritional Science, has spent the last decade collecting and analyzing data from thousands of people with Parkinson’s disease (PD). The result of this monumental effort—a PRO21 Diet Score and a revolutionary perspective—suggests that PD may not be the irreversible, relentlessly progressive condition the world has been taught to believe. Dr. Mishley’s work is based on the idea that the community itself holds the keys to better outcomes. In a project that began as her "side hustle" using the rigorous tools of nutritional epidemiology, she set out to find the success stories among people with PD. Identifying the Positive Deviants: The Power of Modifiable Variables To quantify success, Dr. Mishley first had to build a tool: the Patient Reported Outcomes in Parkinson’s Disease (PRO-PD) scale. This 33-symptom questionnaire allows participants to rate the burden of symptoms like dyskinesia and tremor. A score of zero is universally agreed upon as the goal. Using this scale on data from over 3,500 participants, Dr. Mishley employed the Positive Deviance Model—a strategy used to solve complex problems by studying those who are doing unexpectedly well, not the average. While the general rule is that symptoms worsen (leading to about 10 "good years" post-diagnosis), her data revealed a thrilling secret: after following thousands of people for over a decade, approximately 7% of participants have symptoms that are actually getting better over time. “I don't know what's going on with your neurons, but I'm telling you, I am seeing differences all the time in our own data... It is my opinion based on data that I don't believe this condition is nearly as irreversible or progressive as you have been taught,” Dr. Mishley asserted, driving home how incredibly modifiable the disease trajectory is. A Crucial Caveat: Study Design and Geographic Context It is important to remember that this is an observational study, meaning it can identify strong associations between diet and outcomes, but it cannot definitively prove that one item causes the other. Furthermore, the data collected in the Modifiable Variables in Parkinsonism study is predominantly from North America, meaning the findings should be taken into consideration with this geographic context in mind. For instance, the negative association seen with chicken could potentially be linked to common American farming practices, such as the use of chlorinated chicken washes, which are banned in many other parts of the world. Therefore, environmental or regulatory differences could affect how these dietary findings translate globally. The PRO21 Diet Score: Data-Driven Prescription By comparing the dietary habits of the worst-performing participants with the positive deviants, Dr. Mishley distilled her findings into the PRO21 Diet Score. This 21-point system is based purely on the data collected from thousands of people with Parkinson’s and reveals the strongest dietary factors associated with improvement. Earlier cross-sectional research attempted to create a flexible point system, like a Weight Watchers model, where a "cup of pasta" was "16 points to the worst" and "coconut oil 16 points less symptomatic." That model showed that people who ate olive oil were nine and a half points less symptomatic than those who didn't. However, the comprehensive longitudinal data proved that simple commitment and abstinence were far more effective than trying to "counteract" bad choices. The strategy is simple: eat lots of the stuff in green and best avoid the stuff in red. Scoring Your Diet: The 21 Points The PRO21 Diet Score involves 10 points for adherence (consumption) and 11 points for abstinence (avoidance). Positive Factors (10 Possible Points): Give yourself a point for adhering to each of these requirements over the last 30 days: Organic Food: Buy organically grown food when possible. Home Cooking: Cook most of your own food. Spices: Use spices liberally. Nuts/Seeds: Average at least a half cup of nuts/seeds or 4 tablespoons of nut butter per day. Olive Oil: Average 2 tablespoons of olive oil per day. Fresh Fruit: Get 1 cup of fresh fruit per day. Fresh Vegetables: Get a half cup of fresh vegetables 5 times a week. Non-Fried Seafood: Have non-fried seafood twice a week. Wine: Have two glasses of wine per week. Coffee: Have two glasses of coffee per day. Abstinence Factors (11 Possible Points): Give yourself a point for complete abstinence from each of these items over the last 30 days: Dairy: No milk, cheese, yogurt, butter, ice cream, sour cream, or cottage cheese. Artificial Sweeteners: No Splenda, aspartame (e.g., in chewing gum), or anything labeled "diet." Pork: No ham or bacon. Beef: No beef. Chicken: No chicken. Fried Food: No donuts, french fries, potato or corn chips. Juice: No juice. Sugar: Avoid added sugar. Soda: No soda. Refined Grains: No bread, pasta, pastries, crackers, or processed grains. Canned Food: No food out of a can (canned beans, soup, tomato sauce, etc.). Dr. Mishley noted that most participants score only seven to nine points, which is "part of the problem." Less than 5% achieve the magic spot of 15 points or more. The Unwavering Data on Dairy and Progression Speed The data is uncompromising, particularly regarding animal products. People who are progressing the fastest are eating the most dairy, beef, pork, and chicken. The Dairy Dilemma The data on dairy is particularly stark. Over 18 long-term studies show that the more dairy a non-PD person consumes in their 20s, 30s, and 40s, the more likely they are to develop PD later. Dr. Mishley's study confirmed this effect after diagnosis: every single dairy product (milk, ice cream, yogurt, etc.) is independently associated with worse outcomes and faster disease progression. The negative impact of dairy is so powerful that a chart comparing factors found that dairy is hurting you more than fruits and vegetables are helping you. The single most successful group in the study—the positive deviants—were those who reported complete abstinence from dairy over the study period. When pressed on the mechanism, Dr. Mishley stated that while the definitive why is unknown, the possibilities relate directly to the gut-brain axis, the critical two-way communication pathway between the central nervous system (brain) and the enteric nervous system (gut). Hypotheses include: Pesticide Bioaccumulation: Pesticides in cow feed may be accumulating in the milk and acting as neurotoxins. Gut Microbiome Disruption: Dairy consumption may introduce the wrong kind of microbes into the intestine, promoting the small intestinal bacterial overgrowth (SIBO) and excess methanogens (methane-producing bugs) commonly found in PD patients. This bacterial imbalance creates intestinal inflammation, which sends distress signals up to the brain. Nutrient Interference: Dairy lowers uric acid, a potent antioxidant known to be protective against PD progression, and the combination of dairy protein and calcium can also interfere with the absorption of levodopa. The Power of High Adherence: Translating Scores to Years The scores translate directly to the rate of disease progression and years of good quality of life (defined as a PRO-PD score below 1,000, with below 500 being "excellent"). A person scoring 0 to 5 points gets about 20 good months with Parkinson's before their quality of life starts to significantly decline. A person scoring 10 to 14 points extends that to about 10 good years. People scoring 15 points or more—less than 5% of the study group—are slowing their progression rate by 43% compared to the lowest scorers. This translates to an estimated 18 good years of quality of life. The data is so robust in the 10-to-14-point range that researchers have great confidence in that number, but the 15+ score zone is still being studied as more people adhere. Both motor symptoms and non-motor symptoms (including constipation, apathy, depression, anxiety, and insomnia) improve with better adherence. Dr. Mishley emphasized the difference between cutting back and stopping, likening the necessity of total abstinence for the red-listed foods to the recovery model of Alcoholics Anonymous. Detailed Rationale and Practical Help Dr. Mishley provided detailed context on several variables and offered tools to make the transition easier: Addressing the Trade-Offs Dairy and Osteoporosis: She noted that high-dairy countries often have high osteoporosis rates because the proteins in dairy cause calcium to be excreted. There are many ways to get adequate calcium, Vitamin D, and other nutrients for bone health without dairy. She pointed out that removing dairy and animal products might simply be helping levodopa work better, a pragmatic result regardless of the "why." Spices: Spices are nutritional powerhouses. Using the ORAX scale (which ranks antioxidant content), Dr. Mishley showed that spices like cinnamon (267,000 units), turmeric (159,000 units), and cumin (76,000 units) vastly outperform a red apple (4,700 units). She encourages using them liberally. Canned vs. Frozen: The "Canned Food" point is included partly to avoid people steering toward canned vegetables instead of fresh, as the issue is likely the metal and bisphenol A (BPA) in the can lining, especially with acidic foods like tomatoes. While fresh (raw or cooked) was "awesome," frozen fruits are generally neutral in the data, but frozen vegetables showed a negative association. Wine and Coffee: The data consistently shows that the more wine (especially red) and coffee a person drinks, the better their outcomes. She speculated that this may be due to the high olfactory antioxidants in the smell hitting the brain directly, or that the people who can tolerate drinking still have better glutathione levels. She does not recommend non-drinkers start. Empowering the Community The long-term reward for adherence is not just about the person with PD. The greatest impact is on the next generation: a parent who stops feeding their 15-year-old child dairy and refined foods, steering them toward the PRO21 diet, could potentially delay that child’s projected PD diagnosis by 20 to 25 years. To support this shift, Dr. Mishley offers several resources: Join the Study: Participants are encouraged to join the Modifiable Variables in Parkinsonism study, which requires about an hour and a half twice per year to keep contributing to this life-changing data. PRO Diet Coach (GPT): A free AI tool built into ChatGPT (search for "Mishley" or "Pro Diet Coach") that is programmed with the study data. You can ask it to provide meal plans, analyze your pantry (by photo), or offer tailored advice based on your current score. Parkinson’s School Online: An extensive online educational platform where a special free coupon is provided: PMD-2025. This resource includes hundreds of hours of material, a monthly cooking class, and deep-dive sessions that explain the rationale behind every food variable. The central message is clear: Parkinson's symptoms are highly modifiable, and the path to improvement begins with dietary commitment. The goal is to move from feeling overwhelmed and stressed to feeling empowered, knowing that changing a shopping list can change a life.