It’s Time to Wake Up: The Obesity and Sleep Connection
By: Franklin M. Douglis, M.D.
The obesity epidemic continues unabated, with over 70% of American adults now overweight or obese. If we didn’t already have enough factors contributing to this population health crisis, a wealth of research suggests that poor sleep is also linked to obesity. The sharp increase in obesity in the U.S. over the last few decades is matched proportionately with reduced sleep duration in work-centric capitalist societies – indicating a clear correlation between sleep quality and obesity.
It is well documented that obesity is linked to a host of health issues such as type 2 diabetes, heart disease, certain cancers, osteoarthritis – as well as obstructive sleep apnea (OSA). In obese individuals with OSA, excess weight on the upper chest and neck can block the flow of air, resulting in a pause of breathing, causing people to awaken from sleep choking and gasping for breath. Obese men over 40 years old are especially prone to OSA. Although men are more likely to have OSA than women, after menopause, the risks to women increase sharply- at least partially because of weight gain. Even if a person does not have OSA, obesity degrades sleep quality.
Contrary to popular belief, sleeping is not a sedentary activity. Our brains actually burn more energy during sleep than wake. In addition, our bodies are not really quiescent because multiple essential physiological functions take place during sleep. It is the interruptions of these critical functions that contribute to multiple health problems.
We know we are an obese nation. We also know that diet and regular movement are important for obesity prevention and overall health. However, there is another significant factor that contributes to our ability to achieve and maintain a healthy weight-and that often overlooked factor is sleep.
It’s time that we wake up to the reality: Sleep deprivation is making us fatter, and can severely impact our health
In fact, the association between obesity and sleep apnea is so prevalent that there is actually a medical term for it. “Syndrome Z” describes the fusion of metabolic syndrome (a cluster of conditions including high blood pressure, high cholesterol, elevated triglycerides and large waist circumference) with obstructive sleep apnea. People with obstructive sleep apnea are three times more likely to have a stroke or heart attack, and seven times more likely to die from all causes. Some of these deaths can be attributed to traffic accidents caused by drowsy truck drivers -many of whom are obese and suffer from OSA. Fatalities also occur when people with OSA operate heavy machinery while sleep deprived and exhausted.
Sleep quality has a significant impact on metabolism function. Poor sleep affects leptin and ghrelin, the hormones that control fullness and hunger and regulate energy levels and caloric expenditures. When these hormone levels are disrupted from chronic sleep loss and disturbance, increased appetite and caloric intake lead to weight gain. Additionally, fatigue from sleep deprivation often causes people to reach for a quick “pick-me-up.” For some, grabbing a candy bar from the vending machine provides a temporary burst of energy to compensate for lack of sleep – and the link between excess sugar consumptionand obesity is well established.
Sleep deprivation and obesity lead to a downward spiral: Poor quality sleep contributes to obesity due to hormonal impact and the ensuing fatigue, which can cause increased cravings for fat laden, high-carbohydrate sugary foods. In addition, obesity-induced health conditions such as sleep apnea and arthritis further impact the quality of sleep – producing a vicious cycle of sleep deprivation and further weight gain.
So what is the answer? In addition to making restful and productive sleep a high priority, significant weight loss has shown to improve health conditions directly related to both obesity and OSA, suggesting that achieving and maintaining a healthy weight just might be the answer to treating both.