Sleep and Body Weight: A Close Relationship

“If you weigh too much, maybe you should try sleeping more.”

This commentary in the journal Sleep caught my eye. Flip as it sounds to a person who would sleep more if she could, it points to a relationship between sleep and body weight that should be widely publicized.

Sleep can also affect your ability to keep weight off. As for the relationship between insomnia and body weight, the latest news is surprising. Read on for details:

Insomnia with short sleep increases susceptibility to overweight“If you weigh too much, maybe you should try sleeping more.”

This commentary in the journal Sleep caught my eye. Flip as it sounds to a person who would sleep more if she could, it points to a relationship between sleep and body weight that should be widely publicized.

Sleep can also affect your ability to keep weight off. As for the relationship between insomnia and body weight, the latest news is surprising. Read on for details:

Sleep Deprivation and Weight Gain

It’s established now that sleep deprivation increases feelings of hunger (or interferes with feelings of satiation). Sleep deprivation occurs when sleep is arbitrarily restricted—as it might be during a research project in a sleep lab, when participants’ sleep is restricted to 4 hours a night—or when work or family responsibilities keep you from getting the sleep you need. Either way, the tendency is to eat more. And the more you eat, the more weight you gain.

People who are chronically sleep deprived don’t only tend to put on weight. They also risk developing metabolic syndrome, which is linked to serious medical problems like heart disease and diabetes.

So if the bathroom scale is inching upward every time you weigh yourself, consider not just changes to diet and exercise but also allowing more time for sleep if—and this an important caveat—you’re actually able to get more sleep. A mere 30 minutes more sleep a night can help with weight loss and greatly improve your long-term health.

Short Sleep and Body Weight

People who are short sleepers by nature—those who routinely sleep less (sometimes quite a bit less) than 6 hours a night—are also more susceptible to weight gain and obesity than those whose nights are longer. A study conducted over a period of 13 years showed that every extra hour of sleep duration was associated with a 50% reduction in risk of obesity.

Short sleep is also associated with impaired glucose tolerance and insulin resistance. Thus short sleepers are more at risk for developing diabetes as well.

Sleep Duration Is Not the Whole Story

But routinely shortened sleep is not the only sleep issue associated with weight problems. Research is showing now that sleep quality is related to the ability to lose weight and keep it off.

Unlike sleep duration, which can be objectively measured with polysomnography, sleep quality cannot be assessed objectively. So it’s typically measured with questions similar to these:

  • Do you regularly have trouble sleeping?
  • What’s the overall quality of your sleep?
  • How often do you experience a sense of well-being during the day?

One recent study found that better sleep quality and being a “morning person” correlated with successful weight loss maintenance. Compared with current enrollees in a weight loss program, people who’d lost at least 30 pounds and kept the weight off for at least a year reported significantly better sleep quality and were more often early risers.

In another study, investigators compared people who maintained a loss of at least 10% of their body weight to people who regained their lost weight. Men (but not women) who were successful at shedding pounds and keeping them off reported significantly better sleep quality (but not more sleep) than the weight regainers.

Do Insomniacs Typically Have Weight Problems?

Not necessarily, if results of the latest study can be believed. Researchers in Germany compared the body mass index (BMI) of 233 patients with “severe and chronic insomnia . . . showing objectively impaired sleep quality” to the BMI of 233 age- and gender-matched good sleepers. The results were surprising:

  • BMI, insomniacs: 23.8 kg/m2 (The “normal” BMI range is 18.5 to 24.9.)
  • BMI, good sleepers: 27.1 kg/m2

On average, the chronic insomniacs weighed significantly less than the good sleepers. If confirmed by other research, the result should be somewhat reassuring to those of us concerned about the consequences of insomnia. It would also lend support to the idea that insomnia has less to do with insufficient sleep than with excessive arousal (or hyperarousal) that may affect us 24/7.

Do you find yourself eating more after a couple bad nights?

Sleep Deprived and Gaining Weight

When I’m stressed out, two things happen. One, sleep goes on the lam, and two, I eat to compensate. Last night it was an ice cream cone at Stucchi’s. The night before, I opened a honey jar and had some honey straight up. Move over, Winnie the Pooh!

Sweets and fat are irresistible when I’m feeling sleep deprived, and a new study from UPenn suggests I’m far from abnormal in that regard. The particulars are alarming, so read on.

Eating-Honey2Preparing for a book launch can be stressful, and when I’m stressed out, two things happen. One, sleep goes on the lam, and two, I eat to compensate. Last night it was an ice cream cone at Stucchi’s. The night before, I opened a honey jar and had some honey straight up. Move over, Winnie the Pooh!

Sweets and fat are irresistible when I’m feeling sleep deprived, and a new study from UPenn suggests I’m far from abnormal in that regard. In this study, just five nights of sleep restriction led to a significantly higher intake of calories and weight gain among subjects who were allowed to spend only four hours a night in bed. Short sleep and weight gain apparently go hand in hand.

The particulars are alarming, so read on.

Sleep Restriction Experiment

Researchers monitored 225 subjects—male and female, African American and Caucasian—in a sleep lab for five days. At night, the 27 control subjects could sleep as long as they wished. The other 198 subjects were only allowed to sleep between 4 and 8 a.m. While awake, the subjects spent their time reading, watching TV, and playing video and board games. Exercise was not allowed. Food was available at all times except during testing. Subjects could eat what and when they wanted.

Results

After just five days of sleep restriction,

  • Sleep-restricted subjects gained an average of two pounds, while controls gained a few ounces.
  • Among the sleep-restricted subjects, weight gain was highest among African-American males and lowest among Caucasian females.
  • Sleep-restricted subjects consumed 30 percent more calories than control subjects.
  • Consumption of the extra calories occurred between 10 p.m. and 4 a.m.

The Take-Away

A chronically sleep-deprived lifestyle—particularly one where you have to stay up late at night—sets you up for being overweight. If just five nights of sleep restriction result in a gain of two pounds, what will months and months of short sleep do?

Fortunately my bouts of stress-induced insomnia are rarer than they used to be, so most of the time I’m eating lots of fruit, veggies, fish, and whole grains rather than honey and ice cream. Still, the food cravings I get after just a couple nights of short sleep are so marked that I can’t help but wonder: how much of America’s obesity epidemic is due to poor and insufficient sleep?

What foods are you drawn to when you feel sleep deprived?

Sleep Problems and Weight Gain

I get a serious case of the munchies when I’m feeling sleep-deprived. A few short nights is all it takes to propel me to the places where the good stuff is. I break into the chocolate, corn chips, cheese, and salted nuts with the zeal of a wild pig rooting for truffles, and I eat and eat.

insomnia leading to sleep loss ups your chances of obesityI get a serious case of the munchies when I’m feeling sleep-deprived. A few short nights is all it takes to propel me to the places where the good stuff is. I break into the chocolate, corn chips, cheese, and salted nuts with the zeal of a wild pig rooting for truffles, and I eat and eat.

This reaction to feeling short on sleep is not uncommon, I discovered while conducting interviews for my book. Several insomnia sufferers talked of compensating for lack of energy by overeating and indulging in high-fat comfort foods. Pat, whose high-stress job as a lawyer routinely shortened his nights, felt there was a direct relationship between his insomnia and his weight.

“I’m someone who most of my adult life has been heavier than I want to be,” he said. “When you’re always tired, it’s easier to stress out and harder to be disciplined about eating and working out.”

What the Studies Say

Lots of evidence now links short sleep duration to weight gain and the development of metabolic syndrome (which leads to conditions such as heart disease and diabetes). Research affirms a relationship between sleep deprivation and overeating as well. A recent meta-analysis of the literature on lifestyle factors affecting the drive to eat found that alcohol consumption, sleep deprivation and TV watching significantly increased the short-term drive to eat.*

Another new study suggests that the hormonal factors involved in the increased drive to eat following short sleep may be different in men and women.** Researchers found that restricting subjects’ sleep to 4 hours a night for 3 nights led to

  • increased levels of ghrelin in the men but not the women. Ghrelin is a hunger-stimulating hormone produced in the stomach and the pancreas.
  • reduced levels of GLP-1 in the women but not the men. Produced in the intestine, GLP-1 is a satiety hormone whose levels increase with the eating of meals.

So the men’s response to sleep restriction was to have bigger appetites, and the women’s response was to feel less full. But whether you’re ravenous from the get-go or find it hard to stop eating once you’ve begun, the result is often weight gain and all its unwelcome consequences.

The obesity epidemic today gets blamed on dietary, socioeconomic, environmental, and genetic factors, and lack of exercise. I think more effort ought to go toward exploring the relationship between weight gain and short sleep.