Could getting a good night’s sleep really help you lose weight? Studies continue to suggest that the answer is yes.

In one of the more recent studies, researchers from the University of Murcia in Spain found that poor quality sleep was linked to a higher body mass index (BMI) in a sample of 2,150 adult twins (1). The association was strong regardless of age, gender, education level, physical activity, or smoking habits.

Previously, other large population studies confirm a consistent relationship between a higher BMI and poor quality sleep (2-8). While most of these studies are observational, the scientific literature suggests that poor sleep is linked to greater weight gain.

Chicken Versus Egg: Does Poor Sleep Cause Weight Gain or Vice Versa?

One area of controversy from the epidemiological research has been whether it’s poor quality sleep that leads to weight gain, or if weight gain causes poor quality sleep. The latest twin study from Spain sought to find clues for answering this chicken-versus-egg question.

When the researchers evaluated twins who didn’t share the same BMI, they found a clear link between poor sleep quality and those with a higher BMI. But when they evaluated twins whose sleep quality differed from each other, a link didn’t appear significant with those with a higher BMI as having poor sleep.

From the research, the scientists suggested that poor sleep quality could strongly influence a higher BMI, not the other way around. The use of twins helped to control for possible confounding factors, such as genetics and environment.

Improving Sleep Quality Measures

Scientists rely on a number of criteria to measure sleep quality. These criteria include the length of time it takes to fall asleep, sleep duration, the percentage of time spent asleep versus lying in bed, sleep disturbances, the use of sleep aides (medication), and daytime dysfunction from lack of sleep (9).

There’s no single cause of poor sleep. Genetics, hormones, poor eating and exercise habits, or irregular working hours could all be factors.

Scientists don’t yet understand how poor sleep might cause weight gain. It may be due to changes to metabolism and hormones (10), along with increases in appetite and hunger (11). Or, it might be related to the types of foods people eat late at night (12), or how the body handles food metabolically at nighttime (13).

Regardless of what the cause is for weight gain, the scientific literature suggests that sleep quality should be a priority for those seeking weight loss. Strategies for getting a good night’s sleep might be taking a quality melatonin product, having a satisfying and nutritious snack before bedtime, and keeping your bedroom dark – with phone and tablet screens turned off.

References

  1. Madrid-Valero JJ, Martínez-Selva JM & Ordoñana JR. Sleep quality and body mass index: a co-twin study. J Sleep Res. 2017 Jan 19.
  2. Bjorvatn B, Sagen IM & Øyane N et al. The association between sleep duration, body mass index and metabolic measures in the Hordaland Health Study. J Sleep Res. 2007 Mar; 16(1):66-76.
  3. Cappuccio FP, Taggart FM & Kandala NB et al. Meta-analysis of short sleep duration and obesity in children and adults. Sleep. 2008 May; 31(5):619-26.
  4. Lauderdale DS, Knutson KL & Rathouz PJ et al. Cross-sectional and longitudinal associations between objectively measured sleep duration and body mass index: the CARDIA Sleep Study. Am J Epidemiol. 2009 Oct 1; 170(7):805-13.
  5. Moraes W, Poyares D & Zalcman I et al. Association between body mass index and sleep duration assessed by objective methods in a representative sample of the adult population. Sleep Med. 2013 Apr; 14(4):312-8.
  6. Watson NF, Harden KP & Buchwald D et al. Sleep duration and body mass index in twins: a gene-environment interaction. Sleep. 2012 May 1; 35(5):597-603.
  7. Hung HC, Yang YC & Ou HY et al. The association between self-reported sleep quality and overweight in a Chinese population. Obesity. 2013 Mar; 21(3):486-92.
  8. Kim, M. Association between objectively measured sleep quality and obesity in community-dwelling adults aged 80 years or older: a cross-sectional study. J Korean Med Sci. 2015 Feb; 30(2):199-206.
  9. Krystal AD & Edinger JD. Measuring sleep quality. Sleep Med. 2008 Sep; 9 Suppl 1:S10-7.
  10. Spiegel K, Leproult R & Van Cauter E. Impact of sleep debt on metabolic and endocrine function. Lancet. 1999 Oct 23; 354(9188):1435-9.
  11. Spiegel K, Tasali E & Penev P et al. Brief communication: sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Ann Intern Med. 2004 Dec 7; 141(11):846-50.
  12. Grandner MA, Kripke DF & Naidoo N et al. Relationships among dietary nutrients and subjective sleep, objective sleep, and napping in women. Sleep Med. 2010 Feb; 11(2):180-4.
  13. Miller MA & Cappuccio FP. Inflammation, sleep, obesity and cardiovascular disease. Curr Vasc Pharmacol. 2007 Apr; 5(2):93-102.