Study Finds That Diet May Delay Onset of Parkinson Disease

A recent study found a strong association between Parkinson disease (PD) onset and certain Mediterranean dietary habits. This is the first study to assess whether diet has a link to PD.

The study, published in Movement Disorders, compared the potential effects of 3 diets:

• The original Mediterranean diet (OMeDi), which consists of foods rich in antioxidants and fish and encourages followers to reduce their intake of red meat and dairy products
• The Greek Mediterranean diet (GMeDi), which uses foods similar to the OMeDi but also promotes the consumption of potatoes and limits poultry intake.
• The Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, which rewards followers for their intake of leafy greens, certain berries, and poultry and discourages consuming fried foods, sweets, milk, potatoes, and most fruits.

"There is a lack of medications to prevent or delay Parkinson disease, yet we are optimistic that this new evidence suggests nutrition could potentially delay onset of the disease,” said Silke Appel-Cresswell, MD, study author and an associate professor at the Pacific Parkinson's Research Centre, Djavad Mowafaghian Centre for Brain Health, Division of Neurology, University of British Columbia (UBC), in a statement.

Mediterranean diets have been linked to reduced rates of cancer, cardiovascular disease, Alzheimer disease, and PD. Previous research shows that the MIND diet may reduce Alzheimer disease incidence by 54% and that there is a likely higher cognitive health benefit than the OMeDi. However, this is the first study to examine the effects of the MIND diet in a cohort of patients with PD and compare it with other popular Mediterranean diets.

The researchers gathered self-reported data from 176 participants, 167 of whom had PD and 119 controls. Participants with PD were 68.3% men, with a mean age of 64.9 (8.0) years and a mean disease onset of 6.5 (3.1) years previously. Control participants were 39.3% male, with a mean age of 61.8 (9.9) years. All of the participants were recruited through the Pacific Parkinson’s Research Centre at UBC.

In the cross-sectional study, participants, particularly women, with a high adherence to the MIND diet had a later age of disease onset, experiencing a mean delay of up to 17.4 (range, 15.6-17.4; P ≤ .003) years, than men, whose high adherence contributed to a delay of up to 7.4 (range, 3.6-7.4; P = .21-.01) years.

“Although female participants experienced only slightly larger MeDi effect sizes compared with male participants, the average effect size of the MIND diet in women was more than 3 times that of the men and surpassed all MeDi effect sizes, suggesting that its dietary components may be better suited to delaying PD onset than MeDi in a female-specific manner,” wrote the authors.

The MIND diet was the only diet shown to have an interaction between sex and diet score, despite none of the diets used in the analysis differentiating food intake by sex.

"If we understand the sex differences between the MIND diet and Mediterranean diet then we might better understand the sex differences that drive Parkinson's disease in the first place," said Avril Metcalfe-Roach, lead author of the study and a PhD candidate at UBC's Michael Smith Laboratories.

Female participants were often more adherent to the MIND diet compared with their male counterparts, even after taking into account kilocalorie consumption, which the researchers said may indicate that the higher scores for the MIND diet are not due to differences in food volume.

For men, adherence to the GMeDi had the greatest association with disease onset compared with the OMeDi and the MIND diet, leading to delays of 6.2 to 8.4 years (P = .02-.002). In women, the GMeDi contributed at delays of 8.4 to 9.8 years (P = .05-.03).

The MIND diet had a weak correlation with age of onset, having delayed disease by just 3.6 to 7.4 years (P = .21-.01), and it performed similarly to the onset delay associated with the OMeDi, which was 4.6 to 6.4 years (P = .15-.03) in men.

Study limitations include that the authors’ assumption that dietary habits remained consistent over participants’ lifetimes. They said that future studies should investigate this effect in a larger cohort and should analyze the effect of diet on other PD symptoms, such as gut microbial dysbiosis, disease progression, constipation, and cognition.

Reference

Metcalfe-Roach A, Yu AC, Golz E, et al. MIND and Mediterranean diets associated with later onset of Parkinson’s disease. Mov Disord. Published online January 6, 2021. doi:10.1002/mds.28464