Perspective:

The following are 10 points to remember about the metabolic burden of sleep loss:

1. Observational studies link both sleep quality and duration to metabolic traits.

2. Quality and duration of sleep in this population have been studied with overnight polysomnography and the Pittsburgh Sleep Quality Index.

3. Shift work disrupts the normal circadian sleep wake cycle, and has been associated with adverse metabolic health in large observational studies.

4. Evidence linking sleep loss and metabolic traits include data from large population studies on obesity, diabetes, and dyslipidemia. However, the strongest link is between short sleep and hypertension.

5. A meta-analysis, including more than one million subjects in 16 prospective studies, reported that sleep duration of <7 hours is associated with an increased risk of death (relative risk, 1.12; 95% confidence interval, 1.06-1.38).

6. Reduced sleep duration and sleep quality lead to increased hepatic glucose production and reduced peripheral muscle glucose uptake.

7. Several studies conclude that suppression of slow wave sleep, but not rapid eye movement sleep, impairs glucose metabolism.

8. Activity (measured by actigraphy) is decreased in healthy individuals after one night of partial sleep deprivation. Moreover, habitual sleep deprivation (<6 hours/night) is associated with a significant reduction in total body movement. Taken together, insufficient sleep may negate the positive effects of physical activity on metabolic health.

9. To date, no randomized controlled clinical trial has been reported on an intervention to raise sleep quality and impact positively on metabolic traits. However, at present, physicians can safely encourage good sleep hygiene as a part of good metabolic health.

10. Future studies may target interventions on interruption of distinct physiological mechanisms underlying the link between quality of sleep and metabolic health.