This episode provides an extensive overview of the strong relationship between insufficient sleep and the increased risk of weight gain and metabolic dysfunction. It emphasizes that epidemiological data consistently identify short sleep duration as an independent risk factor for obesity, particularly in younger populations. Mechanistically, sleep deprivation is shown to disrupt appetite-regulating hormones, specifically by decreasing the satiety hormone leptin and increasing the hunger hormone ghrelin, while also impairing glucose metabolism and promoting insulin resistance. Furthermore, experimental studies confirm that restricted sleep leads to increased caloric intake, predominantly from snacks consumed during extended evening hours, resulting in a positive energy balance that favors fat storage. The episode concludes that because the relationship between sleep and obesity is bidirectional, addressing sleep health represents a crucial and modifiable public health strategy for managing metabolic risk.

The sources:

Sanjay R Patel and Frank B Hu. Short sleep duration and weight gain: a systematic review. Obesity, 16(3):643–653, 2008. doi:10.1038/oby.2007.118.

Shahrad Taheri, Ling Lin, Diane Austin, Terry Young, and Emmanuel Mignot. Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index. PLoS Medicine, 1(3):e62, 2004. doi:10.1371/journal.pmed.0010062.

Karine Spiegel, Esra Tasali, Plamen Penev, and Eve Van Cauter. Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Annals of Internal Medicine, 141(11):846–850, 2004. doi:10.7326/0003-4819-141- 11- 200412070-00008.

Esra Tasali, Rachel Leproult, and Karine Spiegel. Reduced sleep duration or quality: relationships with insulin resistance and type 2 diabetes. Progress in Cardiovascular Diseases, 51(5):381–391, 2009. doi:10.1016/j.pcad.2008.10.002.

Arlet V Nedeltcheva, Jennifer M Kilkus, Jacqueline Imperial, Kristen Kasza, Dale A Schoeller, and Plamen D Penev. Sleep curtailment is accompanied by increased intake of calories from snacks. American Journal of Clinical Nutrition, 89:126–133, 2009. doi:10.3945/ajcn.2008.26574.