Planning to Lose Weight in the New Year? Experts Say, "Think Sleep"

Specifically, sleep loss has been shown to affect the secretion of cortisol, a hormone that regulates appetite.(3) As a result, individuals who lose sleep may continue to feel hungry despite adequate food intake. Additionally, sleep loss may interfere with the body's ability to metabolize carbohydrates and cause high blood levels of glucose, a basic sugar.(3) Excess glucose promotes the overproduction of insulin, which can promote the storage of body fat, and can also lead to insulin resistance, a critical feature of adult-onset diabetes.(4)

"Sleep loss is associated with striking alterations in hormone levels that regulate the appetite and may be a contributing factor to obesity," said Michael Thorpy, MD, director of the Sleep-Wake Disorders Center at Montefiore Medical Center in New York. "Any American making a resolution to lose weight in the New Year should probably consider a parallel commitment for getting more sleep."

Weight loss is the number-one New Year's resolution in America,(5) with approximately 40% of the population promising to diet.(6) A nationwide survey found that more than 75% of women between the ages of 25 and 54 make diet resolutions each year or most years.

Unfortunately, nearly 90% of the respondents reported either occasional or no success, with almost half losing little weight or actually gaining weight instead.(5,7)

Sleep Loss Impact on Body Weight
In addition to changes in sleep quantity, reductions in sleep quality can also affect weight. For example, decreased amounts of restorative deep or slow-wave sleep have been associated with significantly reduced levels of growth hormone(1)-a protein that helps regulate the body's proportions of fat and muscle during adulthood.(8) "Sleep loss disrupts a complex and interwoven series of metabolic and hormonal processes and may be a contributing factor to obesity," said John Winkelman, MD, PhD, medical director of the Sleep Health Center at Brigham and Women's Hospital and assistant professor of psychiatry at Harvard Medical School. "What most people do not realize is that better sleep habits may be instrumental to the success of any weight management plan."

Sleeplessness in America
Sleep loss is a common problem in America. According to the 2002 "Sleep in America" Poll sponsored by the National Sleep Foundation,(9) less than one third of adults (30%) reported getting 8 or more hours of sleep per night on weeknights. Only about half (52%) reported getting 8 or more hours of sleep per night on weekends. Although many Americans elect to forgo sleep to increase their leisure or work time, a majority also suffer from sleep disorders that interfere with both the quantity and quality of their sleep. For example, nearly three quarters (74%) reported experiencing at least one symptom of a sleep disorder a few nights per week or more. Insomnia was defined as any of the following four symptoms: difficulty falling asleep, waking a lot during the night, waking up too early and not being able to get back to sleep, and waking up feeling unrefreshed. Fifty-eight percent of respondents reported experiencing at least one symptom of insomnia at least a few nights per week.

"People who experience sleep disturbances for more than a few weeks should see their doctor," said Thorpy. "In addition to making behavioral and lifestyle modifications, there are newer prescription sleep medications that can help individuals fall asleep quickly and increase their total sleep time with minimal next-day effects."