Date Published: January 10, 2018
Publisher: Oxford University Press
Author(s): Haya K Al Khatib, Wendy L Hall, Alice Creedon, Emily Ooi, Tala Masri, Laura McGowan, Scott V Harding, Julia Darzi, Gerda K Pot.
Evidence suggests that short sleep duration may be a newly identified modifiable risk factor for obesity, yet there is a paucity of studies to investigate this.
We assessed the feasibility of a personalized sleep extension protocol in adults aged 18–64 y who are habitually short sleepers (5 to <7 h), with sleep primarily measured by wrist actigraphy. In addition, we collected pilot data to assess the effects of extended sleep on dietary intake and quality measured by 7-d food diaries, resting and total energy expenditure, physical activity, and markers of cardiometabolic health. Forty-two normal-weight healthy participants who were habitually short sleepers completed this free-living, 4-wk, parallel-design randomized controlled trial. The sleep extension group (n = 21) received a behavioral consultation session targeting sleep hygiene. The control group (n = 21) maintained habitual short sleep. Rates of participation, attrition, and compliance were 100%, 6.5%, and 85.7%, respectively. The sleep extension group significantly increased time in bed [0:55 hours:minutes (h:mm); 95% CI: 0:37, 1:12 h:mm], sleep period (0:47 h:mm; 95% CI: 0:29, 1:05 h:mm), and sleep duration (0:21 h:mm; 95% CI: 0:06, 0:36 h:mm) compared with the control group. Sleep extension led to reduced intake of free sugars (–9.6 g; 95% CI: –16.0, –3.1 g) compared with control (0.7 g; 95% CI: –5.7, 7.2 g) (P = 0.042). A sensitivity analysis in plausible reporters showed that the sleep extension group reduced intakes of fat (percentage), carbohydrates (grams), and free sugars (grams) in comparison to the control group. There were no significant differences between groups in markers of energy balance or cardiometabolic health. We showed the feasibility of extending sleep in adult short sleepers. Sleep extension led to reduced free sugar intakes and may be a viable strategy to facilitate limiting excessive consumption of free sugars in an obesity-promoting environment. This trial was registered at http://www.clinicaltrials.gov as NCT02787577.
Sleep is increasingly recognized as a potential modifiable risk factor that may be involved in the complex etiology of obesity and cardiometabolic diseases (1) and is becoming an area of increasing public health concern (2). Observational studies showed links between short sleep duration or poor sleep quality with weight gain (3–5) and its associated cardiometabolic complications (6–11). Today, ∼37% of US adults report sleeping ≤6 h, and less than two-thirds are achieving the recommended 7–9 h/night for optimal physical and mental well-being (12, 13).
This SE RCT had good rates of participation, low rates of attrition, and satisfactory compliance in healthy, free-living adult short sleepers. These results show that a personalized behavioral consultation targeting sleep hygiene is a feasible lifestyle intervention and can be used to test the health effects of SE. Our pilot investigation of secondary outcomes indicates that adherence to advice to extend sleep may reduce free-sugars intake. No effects were observed on indexes of body composition, energy balance, cardiometabolic risk, appetite hormones, or heart rate variability as a result of the intervention.