If you’re trying to lose weight but the scale won’t budge, you might want to take a look at your sleep habits.

Sleep is something we all need but often neglect to prioritize. Getting less than the recommended amount of shut-eye each night can increase your risk of certain health conditions, including obesity.

But what is it about sleep duration — or lack thereof — that may lead to putting on extra pounds?

We’ve partnered with WW (Weight Watchers Reimagined) to go over the science of how sleep habits affect your ability to lose weight, how sleep deprivation impacts your appetite, and the benefits of healthy sleep hygiene.

You might think you’re getting enough sleep — but unless you’re snoozing for at least 7 hours each night most days of the week, you could be falling short of the recommended sleep guidelines for adults.

According to the Centers for Disease Control and Prevention (CDC), adults ages 18 to 60 should aim to get 7 or more hours of sleep each night. This amount increases to 7 to 9 hours of sleep for those ages 61 to 64.

Yet, as of 2014, about 35 percent of American adults were sleeping fewer than 7 hours each night.

According to the Journal of Clinical Sleep Medicine, sleeping fewer than the recommended 7 hours each night can increase your risk of adverse health outcomes like:

  • weight gain
  • obesity
  • heart disease
  • depression
  • stroke

According to a 2013 research review, there’s an association between sleep loss and an increased risk of weight gain and obesity.

Moreover, another small 2013 study found that healthy adults who only slept for 5 hours per night for 5 nights gained an average of 1.8 pounds.

Lack of sleep and appetite control

Eating fewer calories is often the first step to losing weight, if that’s your goal.

But if your appetite hormones (ghrelin and leptin) are out of balance, you may find yourself consuming more food than your body needs.

Ghrelin increases appetite by signaling hunger in your brain, prompting you to eat. Leptin does the opposite by suppressing hunger and signaling fullness in the brain.

When you’re sleep-deprived, your body responds by making more ghrelin and less leptin. This may cause you to overeat.

In fact, an older 2004 study found that ghrelin levels were about 14.9 percent higher in people who slept shorter durations than those who got enough sleep. Study findings also showed that leptin levels were 15.5 percent lower in the group with less sleep.

Sleep deprivation and fighting off cravings

If you find that saying no to less nutritious food is more difficult when you’re short on sleep, you’re not alone.

Results from a small 2016 randomized controlled trial found that a lack of sleep can increase your desire to eat more high calorie foods and decrease your ability to resist them.

More specifically, researchers found that less sleep altered levels of endocannabinoid, which are chemical signals that affect your appetite and your brain’s reward system.

This was most notable on the days participants were sleep-deprived, when endocannabinoid levels were both higher and lasted longer, particularly in the afternoon.

Sleep loss and exercise

Exercise is a crucial component to losing weight, if that’s your goal, as well as to staying healthy. But if you’re not sleeping enough, you may not have the energy to get moving.

Although research on sleep loss and energy expenditure is lacking, sleepiness and fatigue tend to increase sedentary behavior. This, in turn, likely leads to less exercise and physical activity.

Establishing healthy sleep habits can help improve your ability to fall asleep and stay asleep through the night. Here are some tips to get you started:

  • Follow a nightly routine that includes time for relaxing activities like taking a bath, listening to music, or reading.
  • Turn your bedroom into a healthy sleep environment by dimming the lights and setting the thermostat to an ideal sleep temperature of 65°F (18.3°C).
  • Aim to get out of bed in the morning and go to sleep at night around the same time each day.
  • Turn off electronics — including your phone, television, and computer — at least 60 minutes before bedtime.
  • In the evening hours, avoid caffeine, alcohol, and large meals with a high-fat content.
  • Reduce stress levels through mindfulness meditation, deep breathing, and other relaxation exercises.
  • Engage in 30 or more minutes of exercise and physical activity each day.
  • Speak with your doctor if changing your sleep habits doesn’t help or you have concerns about your sleep hygiene.

Diet and exercise are just a small piece of the weight loss puzzle. Getting adequate, quality sleep each night may also impact the number on the scale.

Establishing healthy sleep habits — such as sticking to a sleep schedule, avoiding caffeine before bed, and reducing stress — can help you lose weight and keep it off.