Diet and exercise have long been heralded as the twin pillars of weight loss, but there's a third factor that's often overlooked: quality sleep. 

Research shows that you can undercut your efforts to drop pounds by not logging enough pillow time.

“What has been shown time and time again is if we don't get good sleep, it is harder to lose weight," says psychologist Lauren Broch, who specializes in behavioral sleep medicine and has a master's degree in human nutrition. “I think that's for a lot of reasons—it alters your metabolism, neurotransmitters, hormones, and cells."

HORMONES

Many processes happen in the body while at rest. During sleep, the hormone leptin—which signals when you have enough energy—increases. 

Meanwhile, the hormone ghrelin decreases. This is what tells you when you're hungry or need to store up some fat because you're running low on energy. 

If you don't get enough sleep, you're left with too much ghrelin and not enough leptin, which could cause your brain to send your body the wrong signals, explains Robert S. Rosenberg, a board-certified sleep medicine physician and author of "The Doctor's Guide to Sleep Solutions for Stress and Anxiety."

DECISION -MAKING SKILLS

Sleep affects weight in other ways, too. Consider your decision-making skills when you're exhausted and bleary-eyed: That doughnut probably looks a whole lot more appealing, and there's good reason for that. 

Following sleep restriction, both men and women increase their food intake by 20 percent, snack portion size goes up for those who are already full, and the reward centers in the brain favor calorie-dense foods. 

After reviewing these and other findings, the authors of a 2015 study in the Journal of Health Psychology concluded that treating sleep problems may indirectly improve eating patterns and thus should be considered an important component of a weight-loss plan.

TIMING MATTERS

For those who want to regulate their weight, Broch recommends not only getting ample sleep but consistent sleep. Going to bed at about the same time every night really matters.

“Our bodies are kind of primitive," she says. “We're always trying to override our simple biology, but we need regular sleep and regular calories—a variety of proteins, fats, and carbohydrates—like what primitive people had."

No matter how much we try to outsmart nature, a well-balanced diet and plenty of shut-eye remain critical for optimal health. So the next time you hit the weights at the gym or decide to count calories every morning, just remember—a good night's sleep can make your efforts a whole lot more effective.

Want even better sleep? Sleepers who routinely use their Sleep Number 360^® smart bed features and SleepIQ^® technology get almost 100 hours more proven quality sleep per year.*

Like diet and exercise, quality sleep has a profound impact on our physical, emotional and mental wellbeing. Because no two people sleep the same, Sleep Number 360^® smart beds, with SleepIQ^®  technology, sense your movements and automatically adjust firmness, comfort and support to keep you both sleeping comfortably and provide proven quality sleep. Find your Sleep Number^® setting for your best possible night's sleep, and if you own a Sleep Number^®  bed, log in to your InnerCircle℠ Rewards account to see your exclusive offers, refer friends and more.

*Based on internal analysis of sleep sessions assessing sleepers who use multiple features of Sleep Number^® products. Claim based on sleepers achieving over 15 more minutes of restful sleep per sleep sessions.