Daytime Sleep: A Habit To Avoid And Why

Sleep is essential for good health, but it's possible to get too much of a good thing. While sleep deprivation is often the focus, oversleeping can also be detrimental to your health and could indicate an underlying health condition. So, how much sleep is too much? Sleeping for over nine hours a night may be a sign of a sleep disorder, mental health issue, or other health problem. Consistently sleeping longer than the recommended seven to nine hours for adults can negatively impact your immune system, mental health, heart health, and potentially lead to chronic diseases.

Increased risk of diabetes

Sleep deprivation is a significant public health concern, with around one-third of people in the US not getting the recommended 7 hours of sleep each night. This insufficient sleep has been linked to an increased risk of diabetes.

Insulin Resistance

Several studies have found that sleep deprivation is associated with insulin resistance and glucose intolerance. Sleep loss may alter insulin signalling in adipocytes, which could lead to insulin resistance. Sleep apnea, a common sleep disorder, has also been shown to increase insulin resistance, even in non-diabetic and non-overweight people.

Hormone Imbalance

Sleep deprivation can disrupt the balance of leptin and ghrelin, the hormones responsible for signalling feelings of satiety and hunger, respectively. Sleep-deprived individuals may experience decreased leptin and increased ghrelin, leading to increased hunger and food intake, particularly of calorie-dense snacks. This can contribute to weight gain and an increased risk of diabetes.

Inflammation

Sleep loss has been linked to increased levels of inflammatory markers such as tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). These pro-inflammatory molecules can contribute to insulin resistance and the development of diabetes.

Behavioural Factors

Sleep deprivation can also increase the risk of diabetes through indirect pathways, such as increased caloric intake, impaired decision-making, and unhealthy behaviours. Sleep-deprived individuals may consume more calories, make unhealthier food choices, and engage in behaviours like smoking and excessive alcohol consumption, all of which can increase the risk of diabetes.

Sleep and Diabetes Management

Not only is sleep deprivation a risk factor for developing diabetes, but it can also impact individuals living with diabetes. Poor sleep can lead to unstable blood sugar levels, frequent nighttime awakenings, and difficulty following diabetes self-care recommendations. Therefore, maintaining good sleep hygiene, including a consistent sleep schedule, regular exercise, and a healthy diet, is crucial for individuals with diabetes to manage their blood sugar levels and overall health.

Higher risk of heart disease

Sleep is an essential bodily function that helps us recharge and recover from the strain of our waking hours. During sleep, our heart rate, breathing, and blood pressure all drop to levels below those that occur while we are awake. This period of rest is crucial for maintaining cardiovascular health, and insufficient sleep has been linked to a higher risk of heart disease.

Sleep provides the body with time to restore and recuperate, playing a vital role in almost all aspects of physical health. When we sleep, our heart rate slows, blood pressure drops, and breathing stabilizes. These changes reduce stress on the heart, allowing it to recover from the demands of the day. However, without sufficient nightly sleep, individuals do not spend enough time in the deep stages of non-rapid eye movement (NREM) sleep, which is essential for cardiovascular health.

Chronic sleep deprivation has been associated with several heart problems, including high blood pressure, high cholesterol, heart attacks, obesity, diabetes, and stroke. During normal sleep, blood pressure typically drops by around 10-20%. This nocturnal dipping is essential for cardiovascular health, and non-dipping has been linked to an increased risk of cardiovascular issues. Studies have found that elevated nighttime blood pressure is a stronger predictor of heart problems than high blood pressure during the day.

Additionally, sleep deprivation can lead to weight gain and obesity, which are strongly associated with various cardiovascular and metabolic issues, including hypertension, diabetes, high cholesterol, heart disease, heart attacks, and strokes. Lack of sleep has also been linked to Type 2 diabetes, as it worsens glucose metabolism and impairs the body's ability to process sugar properly.

Furthermore, sleep disorders such as insomnia and obstructive sleep apnea (OSA) can have detrimental effects on heart health. OSA, caused by the blockage of the airway during sleep, can lead to repeated interruptions in breathing, resulting in reduced oxygen levels and increased stress on the heart. People with OSA have been found to have higher rates of coronary heart disease, strokes, and high blood pressure.

In summary, getting adequate, good-quality sleep is essential for maintaining a healthy heart. Sleep deprivation and sleep disorders can increase the risk of various cardiovascular issues, including high blood pressure, heart attacks, and strokes. By prioritizing sleep and addressing any sleep disorders, individuals can reduce their risk of developing heart disease and improve their overall heart health.

Weight gain

Sleep is just as important as diet and exercise when it comes to weight management. Lack of sleep can lead to weight gain in several ways. Firstly, it can disrupt the hormones that regulate hunger and fullness. Sleep deprivation increases the hunger hormone, ghrelin, and decreases the satiety hormone, leptin, leading to increased feelings of hunger and a reduced sense of fullness. This can result in consuming more calories and making poorer food choices, such as opting for high-calorie, fatty, or carbohydrate-rich foods.

Secondly, sleep deprivation can decrease self-control and willpower, making it harder to resist cravings and leading to increased consumption of unhealthy foods. Sleep-deprived individuals may also be less inclined to exercise and more likely to opt for sedentary activities, further contributing to weight gain.

Additionally, insufficient sleep can impact metabolic function. It can lead to a decrease in metabolic rate and fat loss, making it harder to maintain weight loss. Sleep deprivation can also cause a cortisol spike, signalling the body to conserve energy and potentially leading to increased fat storage.

Furthermore, stress is a common cause of both weight gain and poor sleep. Increased cortisol levels due to stress can increase appetite, and individuals may turn to comfort eating to cope with stress, further contributing to weight gain.

Improving sleep quality and duration can help address these issues and promote weight management. Getting adequate sleep can enhance the balance of hormones that regulate appetite and improve metabolic function, leading to better weight control. Additionally, improving sleep can increase energy levels, making it easier to exercise and maintain a healthy lifestyle.

Impaired cognition

Sleep deprivation can have a significant impact on cognitive performance, including impaired attention, memory, and decision-making abilities.

Attention and Working Memory

Both total and partial sleep deprivation can impair attention and working memory. Vigilance tasks, in particular, are affected by sleep deprivation, with individuals experiencing slowed reaction times and increased lapses in attention. Working memory, which is closely linked to attention, is also impacted, leading to difficulties in sustaining attention and processing information.

Long-Term Memory

Sleep plays a crucial role in memory consolidation, and sleep deprivation can disrupt this process. Studies have shown that sleep deprivation can impair both free recall and recognition memory. The ability to form new memories is also hindered, as the brain struggles to process and store new information effectively.

Decision-Making and Judgment

Sleep deprivation can impair judgment and decision-making abilities. Individuals may exhibit rigid thinking and find it challenging to adapt to changing circumstances. They may also become more prone to taking risks and making impulsive choices without fully considering the potential consequences.

Other Cognitive Functions

In addition to the areas mentioned above, sleep deprivation can affect a range of other cognitive functions. These include visuomotor performance, reasoning ability, language skills, and creative problem-solving. Sleep-deprived individuals may also experience microsleep, brief periods of sleep-like activity that can further impair cognitive performance.

Recovery from Sleep Deprivation

The recovery process from sleep deprivation is important to consider. Research suggests that a single night of adequate sleep may be sufficient to reverse the adverse effects of acute total sleep deprivation on cognition. However, chronic partial sleep restriction, which is more common in everyday life, may take longer to recover from, and the brain may need time to adapt and restore normal cognitive functioning.

Individual Differences

It is essential to note that the impact of sleep deprivation on cognition can vary between individuals. Age, gender, and other factors can influence how people cope with sleep loss. For example, older adults may maintain cognitive performance better during short periods of sleep deprivation compared to younger individuals, while women may endure prolonged wakefulness better than men. However, more research is needed to fully understand these differences.

Depression

If you are experiencing symptoms of depression, it is important to seek professional help. A combination of medication and psychotherapy has shown higher rates of improvement than one approach alone. Cognitive behavioural therapy (CBT) and interpersonal therapy (IPT) are both effective treatments for depression. CBT-I, a type of CBT that focuses on managing chronic insomnia, can also be beneficial when sleep issues are a prominent symptom.

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