Healthier dietary patterns are associated with better sleep quality among midlife Mexican women

To evaluate whether dietary patterns are associated with sleep quality in Mexican midlife women.

The study population included 4,467 Mexican women from a longitudinal study of teachers. In 2008, a semiquantitative food frequency questionnaire was administered. Principal components analysis identified 3 dietary patterns: Fruits and Vegetables, Western (meat and processed), and Modern Mexican (tortillas and soda, low in fiber and dairy). Starting in 2012, follow-up questionnaires included the Pittsburgh Sleep Quality Index, which yields a score ranging from 0 to 21 (higher scores = worse quality). Modified Poisson regression analyses examining the association between dietary patterns (categorized into quartiles) and poor sleep quality (score > 5) were conducted, adjusting for socio-demographic and lifestyle confounders and baseline comorbid conditions.

Women were 41.0 ± 7.1 years at baseline, with an average follow-up of 5.5 ± 0.7 years. In fully adjusted models, women in the least-healthy quartile of the Fruits and Vegetables pattern compared with the most were 21% more likely to have poor quality sleep at follow-up (95% confidence interval 1.06, 1.42), while those in the highest quartiles of the Modern Mexican pattern were 23% more likely to have poor quality sleep compared with the lowest quartiles (95% confidence interval 1.06 to 1.43, respectively).

A fruit and vegetable-based dietary pattern was associated with higher sleep quality, while an unhealthier diet pattern was associated with worse sleep quality in midlife women.