Obesity and poor sleep have a compounding relationship that produces non-favorable long-term health outcomes. Recognizing this relationship and implementing strategies that address it enhance patients’ chances of a happier, healthier life.
In an increasingly fast-paced world where we often prioritize productivity over rest, the connection between obesity and sleep becomes a more pertinent topic. While nutrition and physical activity have long been associated with weight management, recent research has shed new light on how obesity impacts our sleep patterns. It’s a complex relationship that goes beyond the surface-level understanding of the disease of obesity. This article delves into the intricate interplay between obesity and sleep, exploring the science behind the connection, the factors contributing to weight gain or loss during sleep, and how making positive changes in patients’ sleep routines can become a powerful tool in the battle against obesity.
A healthy body weight and good sleep hygiene correlate to good health outcomes by providing the patient with adequate physical restoration, regulation of mood, strengthening of immunity, allowance to excrete metabolic waste, and giving time for consolidation of short- and long-term memory.
Obesity and poor sleep are considered to have a compounding relationship to produce non-favorable long-term health outcomes. In June 2022, the American Heart Association included healthy sleep in its Life’s Essential 8 for optimal cardiovascular health. Obesity impacts sleep quality and quantity by disrupting the body’s physiologic processes, which triggers a lack of deep sleep stages, such as N3 Sleep and REM sleep cycles. Obesity also causes an imbalance in the secretion of hormones like ghrelin, leptin, and orexin that control appetite. Insufficient sleep and interrupted sleep patterns compound the effects of abnormal secretion of hunger hormones that are already imbalanced in a patient with obesity.
Understanding the Connection Between Obesity and Sleep Disorders
Several factors link obesity to sleep disturbances, and understanding these connections is crucial for addressing both issues effectively.
The deposition of adiposity and the imbalance of appetite-related hormones in patients with obesity are the main factors that correlate with an irregular sleep-wake cycle and sleep disturbances. Localized adiposity on specific body areas, such as the neck and abdomen, promotes an increase in the effort of breathing during the unconsciousness of sleep and triggers the interruption of standard breathing patterns. Due to these abnormal breathing patterns, the individual suffers from intermittent oxygen deprivation, activation of sympathetic outflow, and frequent short awakenings (called “arousals”), which cause interruptions of N3 and REM brain waves during the sleep-wake cycles as well as the process of detoxifying brain metabolites.
As a baseline, chronic obesity causes an imbalance of appetite-controlling hormones with increased appetite-promoting ghrelin levels and decreased appetite-suppressing leptin levels in the blood. However, in patients with insufficient sleep or sleep disturbances, the increase in the ghrelin to leptin ratio results in a directional worsening of both hormones, causing a deterioration of appetite control and hunger levels.
In the absence of an adequate amount of sleep or the presence of a sleep disorder, poor total sleep time of less than 7 hours or more than 10 hours per 24-hour period has been linked to a significant increase in ghrelin to leptin ratio, increase in hunger level, and worsening of obesity. Mortality rates in patients with obesity are highest in individuals with insufficient sleep of less than 4.5 hours and individuals with hypersomnia with a longer sleep time of more than 10 hours.
From a behavioral standpoint, the likelihood of a high hunger level and unhealthy dietary habits increases among individuals with poor sleep quality.
Types of Sleep Disorders
Obesity is closely linked to several sleep disorders due to the physical and physiological changes that excess body weight can impose on the body. The most common sleep disorders associated with obesity are obstructive sleep apnea, obesity hypoventilation syndrome, insomnia, shift-worker circadian rhythm disorder, and sleep-related eating disorder.
- Obstructive sleep apnea is predominant in patients with obesity in part due to the excess of weight and adiposity around the upper airway, which subsequently results in frequent collapsibility of the oropharynx. This causes a sudden decrease in oxygen supply more than five times per hour of sleep for adults.
- Obesity hypoventilation syndrome or hypercapnic sleep apnea is a common disorder in adults with a BMI of more than 30 kg/m2 or children above the 95th percentile for age and sex. It is characterized by daytime hypercapnia due to a nocturnal lack of ventilation drive or short periods of apnea-hypopnea causing daytime CO2 imbalance.
- Sleep deprivation-type disorders such as insomnia and insufficient sleep disorder are related to an increase in weight gain linked to a rise in ghrelin and a decrease in leptin, increased appetite, and decreased energy expenditure. In some circumstances, the use of sleep aids that promote weight gain, such as diphenhydramine, trazodone, and zaleplon, can increase the prevalence of obesity.
- Shift work circadian rhythm disorder is associated with a high obesity rate. It is believed that the etiology of the disorder and obesity is based on decreased restorative deep sleep, insufficient total sleep time, and inhibition of post-meal ghrelin suppression, which increases hunger and food intake.
- A sleep-related eating disorder is a parasomnia consisting of involuntary eating and/or drinking peculiar or uneatable foods while the patient has a partial or complete loss of consciousness. This parasomnia behavior produces safety concerns and a higher caloric intake, which increases BMI while the patient is not aware of the etiology of their weight gain.
Preparing for sleep as we prepare for every other event in life is essential to preventing and/or treating obesity. Ensuring a regular amount and quality of sleep and recognizing symptoms of sleep disturbances would improve the balance of hunger hormones, increase energy expenditure, and reduce body weight.
The first step for healthcare professionals is to ask about sleep and detect any abnormalities that can predispose the patient to worsening obesity and obesity-related comorbidities. Asking for symptoms such as fatigue, excessive daytime sleepiness, snoring, witnessed apneas, unrestful sleep, difficulty falling asleep, recurrent awakenings, frequent nocturnal micturition, and assessing daytime alertness. Questionnaires assessing sleep in every wellness or initial evaluation are excellent for starting the conversation.
Steps to Take With Patients
Clinicians treating sleep disorders in patients with obesity should adopt a comprehensive approach that addresses both the sleep disorder and the underlying weight issue. Here are some tips for clinicians:
- Use tools such as the STOP-BANG Score, Epworth Sleepiness Scale, and Fatigue Assessment Scale in initial or regular evaluations to open the discussion about obesity, sleep, and health outcomes.
- Ask about sleep frequently during visits. Sleep disorders might not be recognizable to the patient, and in some cases, the symptoms might present suddenly.
- Reinforce sleep hygiene and a consistent sleep-wake schedule of 7-9 hours.
- Refer to a sleep medicine provider if symptoms are consistent with a sleep disorder or if the patient has complex sleep concerns.
The connection between obesity and sleep is profound and multi-faceted. When exploring the intricate interplay between these two factors, it becomes clear that prioritizing healthy sleep habits and weight management is essential for patients’ overall well-being. The impact of sleep on obesity and vice versa cannot be overstated. By recognizing this relationship and implementing strategies for addressing obesity and sleep in patients, clinicians enhance patients’ chances of maintaining a healthy body weight and improving their sleep quality, paving the way for a happier, healthier life.
