Frequent consumption of dairy products appears to be associated with a modest increased risk of Parkinson disease (PD) in women and men, according to a recent study. Analyses were based on data from 2 large prospective cohort studies, the Nurses' Health Study (n=80,736) and the Health Professionals Follow-up Study (n=48,610), with a total of 26 and 24 years of follow-up, respectively. Researchers also conducted a meta-analysis to combine the study with 3 previously published prospective studies on total milk intake and PD risk and 1 study on total dairy intake and PD risk. They found:

• While total dairy intake was not significantly associated with PD risk in these cohorts, intake of low-fat dairy foods was associated with PD risk.
• This association appeared to be driven by an increased risk of PD associated with skim and low-fat milk.
• In the meta-analysis, the pooled relative risk comparing extreme categories of total milk intake was 1.56, and the association between total dairy and PD became significant.