Author:Â C. Small
Are you one of those people who catch a few short hours of sleep each night and spend 18 to 20 hours each day running from here to there with your job, business, family, community work and so forth? If you are, you may be doing more damage to your physical and emotional well-being than what you may realize.
Over the past few decades, sleep researchers across the country have conducted studies which seem to indicate that curtailing sleep and getting poor-quality sleep are implicated in many diseases that affect the entire body, including type 2 diabetes, hypertension, cardiovascular disease, cancer and impaired immune function. One of the most startling observations has come from Dr. Eve Van Cauter* and her University of Chicago colleagues. Over the course of four studies, they showed that people who donâ€™t sleep enough, night after night, unwittingly trigger a hormonal storm that causes their appetites to rise.
Dr. Van Cauter set out to study the connection between sleep loss and appetite after reports from sleep studies indicated that subjects were overeating during extended stays in the laboratory. The common assumption was that they ate because they were bored, but she decided to test that assumption.
In the first-ever study to make the connection between sleep and appetite, published in 2004 in the Annals of Internal Medicine, Dr. Van Cauterâ€™s team brought 12 lean and healthy young men into the lab for two four-hour nights of sleep followed by two 10-hour nights. They found that when the subjects slept for only four hours, they showed dramatic changes in two hormones that regulate appetite. Blood draws revealed an 18 percent decrease in leptin, a satiety hormone produced by the stomach that tells the brain when the body has had enough food. They also showed a 28 percent increase in ghrelin, a hunger-causing hormone produced by our fat cells indicating that our energy reserves are running low and need to be replenished. Taken together, these two hormones boosted the young menâ€™s hunger. The sleep-deprived subjects reported a 24 percent increase in appetite after less sleep, with a special eagerness for chips, cakes and cookies, and breads and pasta.
â€œThis study suggests that there could be long-term consequences with prolonged sleep deprivation â€” especially if youâ€™re trying to control your food intake or stick to a healthy diet,â€ says Kristen Knutson, PhD, whoâ€™s been involved in many sleep studies.
* EveVan Cauter, Ph.D., is an internationally known investigator in circadian rhythms on endocrine system in normal and pathological conditions. She is also an expert in the mathematical and statistical analysis of the temporal patterns of hormonal secretion and the effects of sleep on endocrine function.