An Hour Less of Sleep May Lead to Weight Gain: Study Reveals
Losing just one hour of sleep each night may not seem like a cause for concern, but a recent study suggests that this minor change can affect weight and daily activity levels within just a few weeks.
Researchers concluded that reducing sleep duration by approximately one hour and 20 minutes per day over six weeks was associated with weight gain, increased time spent sitting, and reduced physical activity, according to a study published in the journal *Annals of Internal Medicine* and reported by *mindbodygreen*.
To simulate the sleep patterns many people experience in their daily lives, researchers did not ask participants to stay awake all night. Instead, they gradually delayed bedtime, resulting in each participant losing about 80 minutes of their usual sleep each night.
The study included 95 healthy adult men and women who typically slept between seven and eight hours per night under normal conditions.
Researchers clarified that the goal was not to test the effects of severe sleep deprivation, but rather to determine whether a small, chronic sleep deficit—the most common type among workers and students—could have a noticeable impact on health.
The results showed that participants who slept less gained an average of about half a kilogram during the study period, compared to those who maintained their usual sleep duration.
Researchers also observed that participants became less active during the day, with their daily sitting time increasing by approximately 17 minutes. This increase was higher among men and postmenopausal women, reaching nearly 30 minutes per day.
The study team noted that while these changes might appear limited when viewed in isolation, they could become significant factors in weight gain if sustained over several months or years, especially as physical activity gradually declines.
The findings extended beyond weight gain. Researchers pointed out that previous studies on the same participants showed that chronic sleep deficiency, even if mild, was associated with reduced insulin sensitivity in some women, along with the emergence of inflammatory markers linked to an increased risk of heart disease over time.
Researchers also suggested that lack of sleep may affect multiple pathways within the body. It can disrupt the balance of hormones related to hunger and satiety, reduce energy levels, and make individuals less inclined to move and more prone to consuming larger amounts of food.
The study team emphasized that the results do not imply that losing an hour of sleep will automatically lead to weight gain for everyone. However, they provide additional evidence that adequate sleep is a fundamental component of maintaining health, just as a balanced diet and regular physical activity are.
Researchers concluded that while many people focus on diet and exercise when trying to lose weight, regulating sleep schedules may be an overlooked factor, despite its clear impact on the body over time.
