Sleep deprivation increases the risk of obesity - here is the reason!

Why lack of sleep can lead to obesity

Overweight and obesity are associated with significant health issues. The cause of an excessive weight gain is usually sought in the combination of improper diet and lack of exercise. But also sleep disturbances could form according to a current study a significant risk factor. An international research team found that even a night without sleep has a significant negative impact on the metabolism, increasing the risk of weight gain.

The international research group headed by Jonathan Cedernaes from Uppsala University in Sweden found in the current study that even one night of sleep loss has an influence on the regulation of gene expression and metabolism in humans. This would initiate processes that promote weight gain and muscle breakdown. The scientists published their findings in the journal Science Advances.

Lack of sleep causes changes in the metabolism, which promote weight gain and muscle breakdown. (Image: Sven Vietense / fotolia.com)

Connection between disturbed sleep and weight gain

Previous epidemiological studies have shown that the risk of obesity and type 2 diabetes is significantly higher in people who suffer from repeated sleep deprivation or work shifts, the researchers report. In other studies, a relationship between disturbed sleep and unfavorable weight gain has been demonstrated. "So far, however, it was not known whether sleep loss per se can cause molecular changes at the tissue level, which are an increased risk of unwanted weight gain," the scientists explain in a press release from Uppsala University on the study results.

Tissue samples and blood samples examined

In the new study, the researchers looked at 15 healthy normal-weight individuals who participated in two laboratory sessions where activity and food intake were highly standardized. Participants were allowed to sleep normally (in random order) during a session (over eight hours), and instead were kept awake all night in the second session. The morning after each small tissue samples (biopsies) were taken from the subcutaneous fat and skeletal muscle tissue of the participants. At the same time in the morning, blood samples were also taken to allow comparison between tissue samples and the number of metabolites in the blood. These metabolites include sugar molecules as well as various fatty and amino acids, explain the scientists.

Altered gene expression in adipose tissue

The tissue samples were used for multiple molecular analyzes that demonstrated for the first time that sleep loss leads to a tissue-specific change in DNA methylation, the researchers report. So the gene expression is changed. "It is interesting that we have seen changes in DNA methylation only in adipose tissue, and specifically for genes that have also been shown to be altered in metabolic impairments such as obesity and type 2 diabetes," he said Study leader Jonathan Cedernaes.

Increased fat storage and muscle breakdown

In their investigations, the scientists observed molecular signatures of elevated levels of inflammation in the tissue samples after sleep loss. In addition, specific molecular signatures "suggesting that adipose tissue has increased its ability to store fat after sleep loss, while showing signs of skeletal muscle skeletal muscle protein breakdown, also called catabolism, have been identified," says Cedernaes. In summary, the current study at least partially explains why "chronic sleep loss and shift work can increase the risk of unwanted weight gain and the risk of type 2 diabetes." (Fp)