Short Naps Boost Health, While Sleep Deficit Drives Weight Gain

Health experts say a brief afternoon nap of 10‑20 minutes can improve concentration, memory, mood and lower blood pressure, provided the nap does not exceed 30 minutes. Longer sleep periods during the day may cause grogginess and disrupt nighttime rest.

A separate study found that reducing nightly sleep by about 90 minutes leads to modest weight gain—around 0.5 kg in six weeks—because people sit more, burn fewer calories and experience higher levels of the hunger hormone ghrelin. Over longer periods, chronic sleep loss can raise the risk of obesity, type‑2 diabetes and cardiovascular disease.