Sleep deprivation linked to weight gain
Not getting enough sleep can lead to weight gain, according to a recent Swedish study.
The study suggests that people who don't sleep enough may gain a few pounds due to this habit, but not because they consume more food. At the same time, it's easier for people who do get enough sleep to lose weight.
The reason for this seems to be that lack of sleep slows down the metabolism. As a result, the body burns fewer calories and weight gain ensues.
The study was conducted by scientists at Sweden's Uppsala University. Their findings were published in the American Journal of Clinical Nutrition.
According to Christian Benedict, lead author of the study, the findings show that lack of sleep reduces the energy spent during the day. Based on this information, the researchers concluded that sleep has a role in the regulation of energy expenditure.
This is not the first study to find a connection between lack of sleep and weight gain. Sleep deprivation has also been found to affect stress levels and appetite-regulating hormones. The present study adds more evidence to support the link between losing sleep and gaining weight.
Previous research has shown that people who get less than five hours of sleep per night are more likely to gain weight and develop diseases like type 2 diabetes. But no study proved that lack of sleep could be a direct cause of weight gain and obesity.
The Swedish study consisted of an experiment involving 14 university students, all male. The researchers followed the participants while the latter underwent different sleep conditions: normal sleep, curtailed sleep and no sleep at all.
After a few days, parameters such as the students' food intake, hormone levels, blood sugar and metabolic rate were measured. The results showed a definite link between lack of sleep and a slower metabolic rate (as well as higher levels of blood sugar and of certain hormones).
Even after one night of sleep deprivation, the metabolism was slowed down. The energy spent on activities such as digestion and breathing decreased by 5% to as much as 20%. Disrupted sleep also caused higher levels of blood sugar, stress hormones and appetite-regulating hormones.
However, not getting enough sleep didn't make the participants have more food, so the connection with weight loss doesn't seem to lie here.
Recommendations form the National Sleep Foundation state that an adult should sleep between seven and nine hours per night.
