Dairy Intake linked to Increased Risk of Parkinson’s Disease, finds study

A new study published in the journal of Public Health found that higher dairy consumption, especially milk, is associated with an increased risk of Parkinson’s disease (PD).

Parkinson’s disease affects movement and is characterized by symptoms like tremors, stiffness, and slowed motion. While its exact causes remain unclear, scientists believe a combination of genetic, environmental, and lifestyle factors contributes to its development. In recent years, attention has turned toward diet, especially the potential role of dairy consumption.

This systematic review and meta-analysis examined the relationship between dairy intake and PD risk. This research analyzed data from 9 studies (8 cohort studies and one case-control study) across populations in North America, Europe, and Asia. In total, the cohort studies included over 634,000 participants, among whom more than 4,200 cases of Parkinson’s disease were identified.

The analysis showed that individuals with high total dairy intake had a statistically significant 21% higher risk of developing Parkinson’s disease when compared to those with lower intake. The association appeared stronger in men, who showed a 28% increased risk, while the effect in women was minimal and not statistically significant.

The participants with higher milk intake had a 13% increased risk of Parkinson’s disease, with similar sex-specific patterns as seen in overall dairy consumption. Also, other dairy products (including yogurt, fermented milk, cheese, butter, and ice cream) did not show a meaningful association with PD risk.

These findings suggest that the link may be related to biological mechanisms involving the gut–brain axis. One hypothesis was that dairy intake could influence the gut microbiome in ways that promote the accumulation or spread of alpha-synuclein. 

Despite the findings, this study caution that the evidence is not yet definitive. The included studies were observational, meaning they can identify associations but cannot prove cause and effect. Also, the results varied across populations, and factors such as genetics, lifestyle, and overall diet may influence outcomes.

Overall, the findings of this study emphasize the need for further research involving more diverse populations and clearer distinctions between genetic and non-genetic forms of Parkinson’s disease. They also call for deeper investigation into how specific dietary patterns interact with biological pathways linked to neurodegeneration.

Source:

Yang, D., Nepal, G., Ojha, R., & Tu, Z. (2026). Association between dairy consumption and Parkinson’s disease: A systematic review and meta-analysis. Public Health, 252(106143), 106143. https://doi.org/10.1016/j.puhe.2026.106143