As seniors age, and our metabolism slows down, it’s easy to begin to pack on the extra pounds. Although a healthy diet is key to a successful weight loss plan, medical studies are beginning to reveal that eating right is certainly NOT the only lifestyle factor that impacts weight gain.
Scientists have speculated for some time that sleep helps to regulate metabolism—leading to an optimal weight. A new study, published in the scientific journal Science Advances, discovered the specific impact that losing sleep has on genes that control metabolism.
In fact, just one night of sleep loss plays a role in the regulation of gene expression and metabolism, said the researchers at Uppsala University. The study offers a plausible explanation for how chronic (long-term) sleep loss can lead to an impaired metabolism, weight gain and abnormal disposition of body fat.
Past studies have revealed that those with chronic sleep loss, or people who perform shift work at night, have a higher risk for obesity and type 2 diabetes. Other studies revealed that long term sleep loss resulted in loss of muscle mass and accumulation of fat—simultaneously. But, the new research, conducted at Uppsala, discovered that sleep loss can cause molecular changes at the tissue level—that can increase the risk of weight gain.
In the study, the researchers examined the sleep patterns of 15 healthy people—with normal weight levels. Lab sessions were conducted with very tight control on meal patterns and activity. Randomly, participants slept a normal night of sleep—over 8 hours—during one session, then were kept awake the entire night, during the next session. The morning after each night time session involving an interruption of sleep, small samples were taken from muscle and fat tissue. The results revealed a disrupted metabolism, like that which occurs in obesity and diabetes. The sleep loss tissue samples resulted in changes in DNA mechanisms that regulate gene expression.
According to Jonathan Cedernaes, who led the study, “Our research group was the first to demonstrate that acute sleep loss in and of itself results in epigenetic changes [external modifications to DNA that turn genes “on” or “off “ in the so-called clock genes that within each tissue regulate its circadian rhythm.
“Our new findings indicate that sleep loss causes tissue-specific changes to the degree of DNA methylation [a type of epigenetic mechanism] in genes spread throughout the human genome.” DNA methylation is an epigenetic mechanism that results from chemically altering DNA by adding Methyl (CH3); this results in a change in gene function.
Cedernaes went on to explain that “It is interesting that we saw changes in DNA methylation only in adipose [fat] tissue,” as well as in genes that are involved in metabolic conditions such as obesity and type 2 diabetes. “We therefore think that the changes we have observed in our new study can constitute another piece of the puzzle of how chronic disruption of sleep and circadian rhythms may impact the risk of developing for example obesity,” said Cedernaes.
Changes in response to lack of sleep that were noted by the researchers included:
- A change in how blood glucose (sugar) is handled by proteins in the muscle tissue
- An increase in the body’s capacity to store fat
- An increase in the breakdown of muscle proteins (called catabolism) resulting in muscle loss
- An impairment of glucose (blood sugar) sensitivity (a precursor to diabetes)
- An increase in tissue inflammation (observed in past studies)
Recovery sleep is when a person sleeps more than the recommended hours, after sleep deprivation. Scientific studies are attempting to discover if recovery sleep can reverse the adverse effects of not getting enough sleep.
“It will be interesting to investigate to what extent one or more nights of recovery sleep can normalize the metabolic changes that we observe at the tissue level because of sleep loss. Diet and exercise are factors that can also alter DNA methylation, and these factors can thus possibly be used to counteract adverse metabolic effects of sleep loss,” says Cedernaes.
Maintaining a healthy body weight is part of a successful plan to live well past 100; so, be sure to eat right, exercise, and don’t forget to get plenty of sleep every night!
The scientific journal Science Advances