Study Pinpoints Biochemical Reason Why Insufficient Sleep Can Lead To Weight Gain

Getting too little sleep at night increases the blood levels of an endocannabinoid molecule that stimulates the appetite, a U.S. study finds. Researchers tested the effects of less sleep and normal sleep on nine healthy men (average age 23 years). Participants who slept only 4.5 hours had a higher daytime level of the molecule (2AG) in the blood; those who slept 8.5 hours had lower levels of the molecule. The study provides a biochemical reason why insufficient sleep has been associated in previous studies with increased appetite and weight gain.