(Montreal) Healthy young adults began to gain weight when they were deprived of a good night’s sleep, American researchers have found.
Posted at 9:57 a.m.
Even more concerning, the weight has accumulated in the abdomen, where it is most likely to have a negative impact on cardiovascular health.
“All fats are not equal in their deleterious effects on cardiometabolic health,” commented Dr. Mélanie Henderson, who is a pediatric endocrinologist at CHU Sainte-Justine. Subcutaneous fat is less unfavorable than fat that accumulates at the visceral level, therefore at the abdominal level. »
In a study conducted by researchers at the famed Mayo Clinic in Rochester, Minnesota, 12 young adults between the ages of 19 and 39 were divided into two groups: one who slept only four hours a night for two weeks, and another who slept nine hours, followed by three days of recovery.
The experiment was conducted in a hospital setting so that participants’ sleep, diet and physical activity could be carefully monitored.
The researchers found that the group that was restricted to four hours of sleep consumed an average of 308 calories more per day than the other. After two weeks, this group had gained, on average, 500 grams, and had increased their amount of visceral fat by 11%.
A more detailed analysis then showed that this weight had been added at the level of the abdomen. The amount of visceral fat continued to increase in the sleep-deprived group even after the three-day recovery period.
“The body is built to defend its highest weight,” explained Dr. Henderson. Our hormonal mechanisms are made to maintain our weight. As soon as we lose weight, our metabolism slows down, our signals of satiety change so that we are even hungrier… All these mechanisms are there to defend the weight reached. So when we talk about countering the effects of weight gain, it takes time before we can do it successfully, and it’s often very difficult. »
While the scientific literature strongly documents the link between lack of sleep and weight gain, this study stands out in that it looked at where, specifically, that weight accumulates, Dr. Henderson said.
The study also underlines that the fact of sleeping badly or insufficiently will not have the only consequence of having difficulty getting started the next morning, especially since lack of sleep is a very important in both youth and adults, added Dr. Henderson.
“We know that there is a large percentage of young people who do not get enough sleep, and on average, young people sleep an hour less than 20 years ago,” she said. Many adolescents have deficiencies in the number of hours of sleep at night. »
It will often be video games that take up the time young people don’t spend sleeping, adds Dr. Henderson in conclusion, and studies show that screen time can have an adverse effect on the quality of food. “All lifestyle habits are interconnected,” she said.