A study, published in Science Advances, provides some of the first evidence on how interrupting sleep cycles can directly affect the body’s metabolic processes and lead to long term health risks.
Nurses, pilots and manual workers who have worked the night shift for years are at higher risk of heart disease, diabetes and cancer.
A team of researchers has shown how a single night of poor sleep switches on genes in fatty – adipose – tissue to increase the body’s ability to store fat. They also recorded the opposite effect in muscle tissue as complex proteins – the building blocks of muscle – began to break down into simpler forms. This could be an adaptation to help the body hold on to fat stores it is building up.
15 healthy volunteers each attended a testing session on two occasions, once after a normal night’s sleep and once after staying up all night. They gave samples of fat, muscle tissue, and blood.
After sleep deprivation, people’s fat tissue showed changes in gene activity that are linked to cells increasing their tendency to absorb lipids and to multiply. By contrast, in muscle the scientists saw reduced levels of structural proteins, which are the building blocks the body requires to maintain and build muscle mass.
These findings provide evidence for how chronic sleep loss and shift work may increase risk of obesity and type 2 diabetes, while at the same time decreasing your muscle mass.
Authors think it's important to investigate further to see whether the short-term changes identified were sustained in people working shift patterns or experiencing sleep deprivation over longer time periods.