Successful weight loss maintenance associated with morning chronotype and better sleep quality.

It is not known whether individuals successful at long term weight loss maintenance differ in chronotype (i.e., being a "morning" or "evening" person) or sleep habits compared to those who are overweight and obese. We compared Morningness-Eveningness Questionnaire (MEQ) and Pittsburgh Sleep Quality Index scores of 690 National Weight Control Registry (NWCR) members (73 % female, 93 % white, age = 51.7 ± 12.5, BMI = 26.4 ± 5.1) to 75 enrollees in two behavioral weight loss interventions (INT; 77 % female, 88 % white, age = 55.7 ± 10.4, BMI = 36.2 ± 4.7). Controlling for age, MEQ scores were higher in NWCR than INT, p = .004, such that more NWCR than INT were morning-types and fewer were evening types, p = .014. Further, NWCR participants reported better sleep quality, longer sleep duration, and shorter latency to sleep onset compared to INT, ps < .05, and fewer NWCR participants reported <6 or <7 h of sleep, ps < .01. Future studies should examine if these factors change as a result of weight loss or are predictors of weight outcome.