title: Diet and Parkinson's disease: a potential role of dairy products in men.
abstract: Diet may play a causative role in Parkinson's disease (PD), but potential associations between diet and PD risk rarely have been assessed in prospective studies. We investigated associations between food intakes and PD risk in two large prospective cohorts in which 210 incident PD cases in men and 184 in women were documented. A positive association was found between dairy intake and PD risk in men (relative risk [RR] comparing extreme categories, 1.8; p trend = 0.004), but not in women (RR, 1.1; p trend = 0.9). No other food groups were associated with PD risk in either men or women. Further analyses among men showed significant positive associations with PD risk for intakes of several dairy foods as well as dairy calcium (RR, 1.5; p trend = 0.02), dairy vitamin D (RR, 1.6; p trend = 0.004), dairy protein (RR, 1.6; p trend = 0.01), and lactose (RR, 1.8; p trend = 0.002), but not dairy fat (RR, 1.1; p trend = 0.4). Intakes of calcium, vitamin D, and protein from other dietary or supplemental sources were not related to PD risk in men. Our results suggest that higher intake of dairy products may increase the risk of PD in men; however, this finding needs further evaluation, and the underlying active components need to be identified.
authors.affiliation: Department of Nutrition, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115, USA. hchen@hsph.harvard.edu
authors.forename: Honglei
authors.initials: H
authors.lastname: Chen
authors.forename: Shumin M
authors.initials: SM
authors.lastname: Zhang
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Hernán
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
authors.forename: Alberto
authors.initials: A
authors.lastname: Ascherio
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D016001:Confidence Intervals; D003611:Dairy Products / Q000009:adverse effects* / Q000706:statistics & numerical data; D004032:Diet / Q000009:adverse effects* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010300:Parkinson Disease / Q000453:epidemiology*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors