Sleep extension is a feasible lifestyle intervention in free-living adults who are habitually short sleepers: a potential strategy for decreasing intake of free sugars? A randomized controlled pilot study

Abstract

Background: 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.

Objective: 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.

Design: 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.

Results: 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.

Conclusions: 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 www.clinicaltrials.gov as NCT02787577.

Keywords: RCT; diet; energy balance; energy intake; randomized controlled trial; sleep extension.

FIGURE 1

Illustration showing the 4-wk sleep extension parallel, randomized-controlled research design. Baseline and endpoint measures were collected before randomization and within the last week of the trial, respectively. Body Comp, body composition; BP, blood pressure; DVP, digital volume pulse; RMR, resting metabolic rate; TEE, total energy expenditure; WA, wrist actigraphy.

FIGURE 2

CONSORT diagram of the SLuMBER study. CESD, Center of Epidemiologic Studies–Depression scale; CONSORT, Consolidated Standards of Reporting Trials; ISI, Insomnia Severity Index; SLuMBER, Sleep Lengthening and Metabolic health, Body composition, Energy balance and cardiovascular Risk Study.