Sleep deprivation affects fat metabolism and increases risk of weight gain

Lack of sleep affects how the body metabolizes fat, leading to feeling less full after eating. This predisposes individuals to put on more weight, suggests a study published in the Journal of Lipid Research.

Sleep deprivation is a very common problem among adults. According to the American Sleep Association, about 50 to 70 million American adults suffer from a sleep disorder, a type of which is sleep deprivation. The risk of diseases also increases as a result of sleeping less than the recommended number of hours – that is, at least seven hours for individuals 18 years old and above.

For the study, researchers from Pennsylvania State University and the Harvard Medical School looked at the effect of sleep deprivation on fat metabolism. Previous research primarily focused on its effect on glucose metabolism, which is important for diabetes. However, few studies assessed the digestion of lipids, or fats, from food.

Lack of sleep affects fat metabolism

The researchers recruited 15 healthy male individuals in their 20s. The participants spent one week getting plenty of sleep at home before checking into a sleep lab for 10 nights. For five nights, they slept for no more than five hours. The researchers interacted with the participants, playing games and talking to them to keep them awake and engaged.

The team administered a standardized high-fat dinner – a bowl of chili mac – after four nights of sleep restriction and then compared blood samples taken from the study participants. They found that sleep deprivation caused lipids to be cleared more quickly from the blood after a meal, which could increase weight gain. Furthermore, the participants reported feeling less full after a meal.

Two nights later, the participants were allowed to sleep 10 hours to catch up on missed sleep. After the first night, they ate one last bowl of chili mac. The researchers found that despite improved fat storage after a night of recovery sleep, the participants did not return to the baseline, healthy level.

Despite some limitations, such as the highly controlled set-up and the participants being all male and healthy, the study demonstrates the importance of sleep to metabolic health, particularly to fat metabolism. Furthermore, the findings reiterate the danger of eating excessive unhealthy fats, a dietary practice that is widespread among Americans.

“A high-fat meal in the evening, at dinnertime, and real food, not something infused into the vein? That’s a typical exposure. That’s very American,” said first author Kelly Ness.

Sleep deprivation linked to obesity

Lack of sleep is a risk factor for obesity. In fact, three to five percent of the overall proportion of adult obesity can be attributed to sleep deprivation.

In the Nurses’ Health Study, one of the largest investigations into the risk factors for major chronic diseases in women, researchers found that sleep deprivation predisposes women to obesity. They followed about 60,000 women for 16 years, collecting information about their diet, weight and sleep habits, among other aspects of their lifestyle.

All of the women were healthy and none were obese at the start of the study. After 16 years, those who slept five hours or less per night had a 15 percent higher risk of becoming obese, compared to women who slept seven hours per night. Short sleepers also had a 30 percent higher risk of gaining 30 pounds over the study duration. (Related: Proper sleep hygiene is a must, since your body burns calories even in sleep.)

According to experts, sleep deprivation increases obesity risk in a variety of ways. People without adequate sleep may be too tired to exercise or they may be consuming more calories simply because they are awake longer and have more opportunities to eat. Sleep deprivation may also disrupt the balance of key hormones that control appetite, increasing feelings of hunger among sleep-deprived individuals.

Although it can be very difficult to achieve a full night’s sleep, these studies emphasize the importance of sleep. In matters of health, what’s good for the body should always be prioritized.

For more tips for a good night’s sleep, visit MindBodyScience.news.

Sources include:

IntegrativePractitioner.com

SleepAssociation.org

JLR.org

HSPH.Harvard.edu