Diet quality in young adulthood and sleep at midlife: a prospective analysis in the Bogalusa Heart Study.

Background: Diet and sleep are both established risk factors for cardiometabolic diseases. Prior evidence suggests a potential link between these behaviors, though longitudinal evidence for how diet associates with sleep is scarce. This study aimed to determine the prospective association between diet quality in young adulthood and multiple sleep outcomes at midlife in the Bogalusa Heart Study (BHS).

Methods: This prospective study included 593 BHS subjects with dietary assessment at the 2001-2002 visit and sleep questionnaire responses from the 2013-2016 visit, after an average of 12.7 years (baseline mean age: 36 years, 36% male, 70%/30% White and Black persons). A culturally tailored, validated food frequency questionnaire assessed usual diet. Diet quality was measured with the Alternate Healthy Eating Index (AHEI) 2010, the Healthy Eating Index (HEI) 2015, and the alternate Mediterranean (aMed) dietary score. Robust Poisson regression with log-link function estimated risk ratios (RR) for insomnia symptoms, high sleep apnea score, and having a healthy sleep pattern by quintile and per standard deviation (SD) increase in dietary patterns. Models adjusted for potential confounders including multi-level socioeconomic factors, depression, and body mass index. Trends across quintiles and effect modification by sex, race, and education were tested.

Results: Higher diet quality in young adulthood, measured by both AHEI and HEI, was associated with lower probability of having insomnia symptoms at midlife. In the adjusted model, each SD-increase in AHEI (7.8 points; 7% of score range) conferred 15% lower probability of insomnia symptoms at follow-up (RR [95% confidence interval CI]: 0.85 [0.77, 0.93]), those in Q5 of AHEI had 0.54 times the probability as those in Q1 (95% CI: 0.39, 0.75), and there was a significant trend across quintiles (trend p = 0.001). There were no significant associations between young adult diet quality and having a high sleep apnea risk or a healthy sleep pattern at follow-up.

Conclusions: A healthy diet was associated with a lower probability of future insomnia symptoms. If replicated, these findings could have implications for chronic disease prevention strategies incorporating the lifestyle behaviors of sleep and diet.