Sleep deprivation (4 consecutive nights) increases the body’s endogenous production of cannabinoids, which contributes to excessive food intake and the link to obesity.

noli's read

This mechanism is based on recent studies, notably a study published in 'SLEEP' (Hanlon et al., 2016), which demonstrated that sleep restriction increases circulating levels of 2-arachidonoylglycerol (2-AG), an endocannabinoid, in humans. This evidence is robust as it is a randomized controlled trial (RCT) showing a direct biological link between sleep deprivation and appetite signaling. Matthew Walker’s explanation is faithful to this research, adding that this complements the already known hunger regulation mechanisms via leptin and ghrelin. There is no exaggeration here, as the study explicitly highlights that this increase in cannabinoids makes the experience of eating more rewarding, thereby promoting snacking. This biological process offers an elegant explanation of how the brain 'pushes' toward increased caloric intake after a bad night's sleep. The evidence is therefore consistent and well-documented scientifically.

the sources

1. 1Spiegel K, Tasali E, Penev P, Van Cauter E. 2004
2. 2Al Khatib HK, Harding SV, Darzi J, Pot GK. 2016