Check out this answer from Consensus:
The optimal amount of sleep varies among individuals, but most adults need between 7 to 9 hours of sleep per night to maintain good health. Chronic sleep deprivation can lead to a range of health issues, including increased food intake, impaired weight loss efforts, higher risk of Alzheimer’s disease, decreased cognitive performance, hormonal imbalances, and reduced insulin sensitivity. Prioritizing adequate sleep is essential for overall health and well-being.
Sleep is a fundamental aspect of human health, influencing various physiological and psychological functions. Despite its importance, many individuals do not get sufficient sleep, leading to a range of health issues. This article explores the optimal amount of sleep needed for maintaining good health and the consequences of sleep deprivation.
The Importance of Adequate Sleep
Adequate sleep is crucial for maintaining overall health and well-being. It plays a vital role in various bodily functions, including metabolism, cognitive performance, and emotional regulation. Research has shown that insufficient sleep can lead to significant health problems, including obesity, diabetes, and impaired cognitive function.
Effects of Sleep Deprivation on Health
Increased Food Intake and Obesity
One study found that acute partial sleep deprivation led to increased food intake in healthy men. Participants who slept for only 4 hours consumed 22% more calories the following day compared to when they had 8 hours of sleep. This increase in caloric intake was accompanied by higher levels of hunger before meals, suggesting that sleep restriction could promote obesity1.
Impaired Weight Loss Efforts
Another study demonstrated that insufficient sleep undermines dietary efforts to reduce adiposity. Participants who had only 5.5 hours of sleep per night lost less fat and more fat-free body mass compared to those who had 8.5 hours of sleep. This indicates that lack of sufficient sleep may compromise the efficacy of dietary interventions for weight loss2.
Risk of Alzheimer’s Disease
Sleep deprivation has also been linked to an increased risk of developing Alzheimer’s disease. A study found that one night of total sleep deprivation interfered with the physiological decrease in cerebrospinal fluid β-amyloid 42 levels, a key protein in Alzheimer’s disease pathology. Chronic sleep deprivation may elevate the risk of Alzheimer’s disease by increasing cerebral β-amyloid levels3.
Decreased Vigilance and Cognitive Performance
Chronic sleep curtailment, even without extended wakefulness, degrades human vigilance performance. Participants who experienced chronic insufficient sleep showed significant impairments in neurobehavioral performance, including reaction time and attention lapses. These impairments were observed throughout the day, indicating that chronic insufficient sleep affects performance regardless of the time of day4.
Hormonal Regulation and Appetite
Sleep duration also affects hormonal regulation of appetite. Short sleep duration was found to increase fasting and morning ghrelin levels in men, which could predispose them to overeating. In women, short sleep reduced afternoon levels of GLP-1, a hormone that promotes satiety. These hormonal changes suggest that short sleep may lead to overeating through different mechanisms in men and women5.
Insulin Sensitivity and Diabetes Risk
Short sleep duration is associated with impaired glucose tolerance and an increased risk of diabetes. A study found that one week of sleep restriction (5 hours per night) significantly reduced insulin sensitivity in healthy men. This reduction in insulin sensitivity raises concerns about the long-term effects of chronic insufficient sleep on metabolic health7.