Poor sleep quality, later bedtime influence glucose level after breakfast
Poor sleep quality and a later bedtime are associated with a more pronounced postprandial glycemic response to breakfast the following morning, according to an analysis published in Diabetologia.
“While there have been numerous large prospective cohort studies focused on the relationship between self-reported sleep, disease and well-being, objective data on sleep and postprandial glucose metabolism typically comes from small studies conducted in tightly controlled settings and in specific population subgroups, such as those suffering sleep disturbances owing to pregnancy, sleep apnea, depression, obesity or diabetes,” Paul W. Franks, PhD, professor of genetic epidemiology at Lund University Diabetes Centre in Malmö, Sweden, and colleagues said in a press release. “Because of this, there is a need for greater evidence of the effects of sleep on glucose metabolism in healthy individuals.”
Franks and colleagues analyzed data from 953 healthy adults (41% twins) from the United Kingdom and the United States who participated in the PREDICT dietary intervention trial between June 2018 and May 2019. Over 2 weeks in the clinic and at home, participants consumed eight standardized meals of different nutritional composition in randomized order: metabolic challenge meal; medium fat and carb; high fat 35 g; high carb with low fat and protein; a 75 g oral glucose tolerance test, consisting of carbohydrates only; high fiber; high fat 40 g; and high protein. Participants were asked to consume only their standardized breakfasts within 10 minutes after no less than 8 hours of fasting. Actigraphy was used to assess sleep duration, efficiency and timing, and continuous glucose monitors were used to measure glycemic variation across 8,000 meals.
Researchers found sleep variables were significantly associated with postprandial glycemic management for between- and within-person level, as measured by 2-hour incremental area under the curve. Sleep period time interacted with meal type, with a smaller effect of poor sleep on postprandial blood glucose levels when high-carbohydrate breakfasts (P for interaction = .02) and high-fat breakfasts (P for interaction = .03) were consumed compared with a reference 75 g OGTT.
Researchers observed a similar interaction for within-person sleep period time, with smaller effects seen on postprandial glucose after high carbohydrate breakfasts (P for interaction = .001) and high fat breakfast (P for interaction = .02).
Within- and between-person sleep efficiency were associated with lower postprandial blood glucose levels irrespective of meal type (P < .03 for both). A later sleep midpoint, defined as the time deviation from midnight, was associated with higher postprandial glucose for both between-person and within-person comparisons (P = .035 and P = .051, respectively).
“While sleep is generally recognized as one of the pillars of good health, the data reported here suggest that one-size-fits-all sleep recommendations are suboptimal, particularly in the context of postprandial glycemic control, a key component of diabetes prevention,” the researchers wrote. “By analyzing both between-person and within-person effects, this study provides unique and powerful insights into both population-level and person-level effects of sleep on metabolic health. Notably, our data suggest that sleep duration, efficiency and midpoint are important determinants of postprandial glycemic control at a population level, while illustrating that to optimize sleep recommendations it is likely necessary to tailor these to the individual.”