Too little sleep can affect hormones and metabolism in ways that promote diabetes.

In the past decade, there has been growing evidence that too little sleep can affect hormones and metabolism in ways that promote diabetes. According to a study published in the Lancet in 1999, healthy men with a week of impaired sleep –- only four hours a night –- showed dramatic changes in glucose tolerance. They also had higher-than-normal glucose levels after just one week. This study involved healthy people with no previous record of insulin resistance or history of diabetes.

For those already diagnosed with diabetes, sleep deprivation leads to extremely poor blood sugar control. These studies do not include control factors of the snowball effect that often starts with losing a night's sleep. Sleepy people don't usually reach for healthy foods as snacks and meals. They don't usually choose to walk during their lunch break -– or head to the weight room after work. Tight glucose control involves nutrition and exercise parameters, and both of those are adversely affected by just one night of impaired sleep.

If you’re skimping on sleep to wake up extra early and squeeze in a workout, you may be doing your body more harm than good. A study published in Sleep Medicine Reviews showed that even partial sleep loss leads to a deregulation of appetite control and can even increase your risk for obesity and diabetes.

Diabetes and Sleep: What's the Connection?

In the past decade, there has been growing evidence that too little sleep can affect hormones and metabolism in ways that promote diabetes, Knutson tells WebMD.


She cites a 1999 Lancet study by colleagues at the University of Chicago. The researchers monitored the blood sugar levels of 11 healthy young men who were allowed only four hours of sleep per night -- from 1 a.m. to 5 a.m. -- for six nights.

"That study showed that after only a week of short bedtimes, their glucose tolerance was impaired. There could be dramatic effects even after only a week," according to Knutson

After 6 nights of little sleep, the men had higher-than-normal blood sugar levels. (The levels were not high enough to be diagnosed as diabetes, however). The effects went away once the men were back on their normal sleep schedule.

Experts also believe that chronic sleep deprivation may lead to elevated levels of the stress hormone, cortisol. Elevated cortisol may in turn promote insulin resistance, in which the body can't use the hormone insulin properly to help move glucose into cells for energy.

"That is on the pathway to developing diabetes," Knutson tells WebMD.

Further, research shows that sleep loss reduces levels of the hormone leptin, an appetite suppressant, while boosting levels of ghrelin, an appetite stimulant. That's a poor combination that may prompt sleep-deprived people to eat more.

And most sleep deprived people don't snack on fruits and vegetables, Knutson points out. Instead, they tend to crave high-carbohydrate foods, such as salty, fatty potato chips. This is not just bad for your waistline, but also your diabetes outlook.

"If you add overweight to the mix, you could possibly increase your risk of developing diabetes," Knutson says.

Pay attention to what you eat and drink before bedtime. Try not to go to bed ravenous or stuffed. Be aware that a glass of wine might help calm the nerves, but metabolizing alcohol keeps the body in an alert mode while the mind is trying to snooze. Have that glass of wine earlier in the evening. And yes, eating bad pizza right before bed can cause nightmares. So can stuffing yourself with any food minutes before trying to sleep. Your body is trying to do two things: metabolize food and sleep. The food is going to win, and that's a cause for dreams and other disruptions to quality sleep.