Though weight gain has many causes, few people would guess that one of them is lack of sleep. But those who deal with sleep disorders understand that shift workers are at higher risk for weight gain than those who work normal daylight hours.
Because night shift workers typically get two hours less sleep than day workers, they're often more susceptible to being "out of sync" with their own internal circadian clock, meaning "they can't sleep when they're supposed to and can't stay awake when they're supposed to," said Dr. Howard Leaman, a sleep disorders specialist at LDS Hospital's Intermountain Sleep Disorders Center.
He and Dr. Robert Mazzola, a fellow sleep specialist at the center, will answer questions about all kinds of sleep disorders, symptoms and treatment during Saturday's monthly Deseret News/Intermountain Healthcare Hotline, which runs from 10 a.m. to noon. The questions are confidential and will not be broadcast. Call 801-236-6061 or 1-800-925-8177 to ask a question.
No matter how long someone has been working the overnight shift, the human body's wake and sleep cycle is operating, trying to get people to sleep at night and work during the day.
"During the wake cycle the body temperature is higher, and brain function and hormones activate that help manage the physical demands" that come with being awake. When night time comes, the process reverses itself because "the strongest cue (for wakefulness) is light," Leaman said.
Those who become out of sync with their own internal clock are at risk, not only while driving or on the job, but with their overall health, because they have a "decreased ability to sense the appetite suppressant hormone" that helps regulate food intake and tells people when they've had enough to eat.
"You may have noticed that people on the night shift are often overweight or obese," he said, noting sleep deprivation can be the cause because the foods they crave "are sweet or contain fat. The less sleep you get, the more you crave junky foods."
Weight isn't the only issue those who are out of "sleep sync" have to deal with. Night shift employees also have challenging social schedules because they struggle to care for their children in the same way they could if they weren't so sleep deprived, he said.
"They often take things like stay-awake medications, or they use alcohol or caffeine to help deal with that," all of which can create other kinds of problems that exacerbate the lack of sleep, Leaman said.
Most people need at least seven hours of sleep at night to function at their best, though "you can get by on six briefly. But if you only get four, you're not doing well."
In fact, with only four hours of sleep, "your ability to drive deteriorates to the point that it's like you're at twice the legal limit for blood alcohol," he said, which means sleepy drivers are often more impaired than those who've had too much to drink.
"It's a major issue, but there's not breath test for sleepiness," Leaman said.
The risk becomes even more complicated for someone who takes medication for sleep apnea, he said. In one study, "of those with sleep apnea who were given sleeping pills, 50 percent of them had a crash in their history," while the patients with sleep apnea who didn't take pills to sleep posted a much lower history of accidents, he said.
To determine whether there is a sleep disorder present, people should consider consulting with their primary care physician about initial symptoms and be evaluated in a sleep clinic if a lack of sleep has become problematic.
"People need to know that many times their perception of their sleep may be different from how they actually sleep. It's governed not only by time of day but by how much sleep you have had. When you're deprived of sleep, the body will take sleep whenever it can," including at stop lights or while driving, Leaman said.
"The bottom line is, sleep is so tied with all other body functions that if you're sleeping well it's a good sign of your health. If you're not doing well, you often have a problem sleeping."
Doctors answer your calls
Sleep disorders and treatments is the topic of today's Deseret News/Intermountain Healthcare Hotline. From 10 a.m. to noon, Drs. Robert Mazzola and Howard Leaman, sleep disorders specialists at LDS Hospital's Intermountain Sleep Disorders Center, will answer questions by phone. Call 801-236-6061 or 1-800-925-8177.