Eating More Legumes, Nuts in Postmenopause Lowers Incident Insomnia Risk

Postmenopausal women with a better diet quality are at lower risk for insomnia, according to results of a study published in Sleep.

Researchers from Columbia University Irving Medical Center analyzed data from 74,513 postmenopausal women participating in the Women’s Health Initiative Observational Study to determine whether adherence to healthful dietary patterns lowers the risk of developing insomnia.

Participants completed a Food Frequency Questionnaire at baseline, and dietary quality scores were calculated based on adherence to the alternate Mediterranean and Dietary Approaches to Stop Hypertension (DASH) diets. Insomnia was assessed using the Women’s Health Initiative Insomnia Rating Scale at baseline and after 3 years.

[E]ndorsing healthful dietary patterns is associated with a lower risk of insomnia in postmenopausal women, the population most prone to poor sleep.

The women had a mean (SD) age of 63.5 (7.3) years and a mean (SD) BMI of 27.1 (5.7) kg/m²; 88.19% were White. At baseline, 22,551 women reported insomnia, and 9349 new cases developed during follow-up. Compared with those with poor adherence to the Mediterranean or DASH diets, women with better adherence tended to have healthier profiles, including lower BMI, higher physical activity levels, and a lower prevalence of hypertension and type 2 diabetes.

Incident insomnia at 3 years was less likely among individuals with good adherence to the alternate Mediterranean (adjusted odds ratio [aOR], 0.925; 95% CI, 0.879-0.974; P =.003) or DASH (aOR, 0.937; 95% CI, 0.891-0.985; P =.01) diet. Similarly, risk for insomnia decreased with each standard deviation increase in diet score for the alternate Mediterranean (aOR, 0.963; 95% CI, 0.938-0.989; P =.006) or DASH (aOR, 0.960; 95% CI, 0.935-0.986; P =.001) diets.

These associations were largely driven by the consumption of nuts and legumes, as participants with higher intake showed a 5.7% lower odds of developing insomnia (aOR, 0.943; 95% CI, 0.895-0.993; P =.02). In contrast, intake of low-fat dairy, sodium, red and processed meat, and sugar-sweetened beverages was not associated with insomnia risk.

Study limitations include an observational design and self-reported data.

The study authors concluded, “[E]ndorsing healthful dietary patterns is associated with a lower risk of insomnia in postmenopausal women, the population most prone to poor sleep.”