What is Core Sleep? The Impact of Sleep on Your Health

Strengthens your immune system, memory, cognitive powers, and mood regulation. Core sleep is essential for physical and mental health. This phase is vital for physical restoration, memory consolidation, and maintaining metabolic health. What is core sleep? Core sleep refers to the essential portion of sleep that is crucial for restorative bodily functions, primarily encompassing deep non-rapid eye movement (NREM) sleep, also known as slow-wave sleep (SWS). As per a report shared on Wikipedia, researchers from the University of Chicago Medical Center followed 11 young, healthy men for 16 consecutive nights. For the first 3 nights, they slept the normal 8 hours, then for about 4 hours the next 6 nights, and the next 7 nights they slept even longer, spending 12 hours in bed.

This created some sort of pre diabetic conditions in them, it took about 40% longer to digest glucose levels after a high-carbohydrates meal. This happened just because of the sleep deprivation which lowers down the thyroid stimulating hormone and instead produce an increased amount of cortisol (stress hormone) and can create insulin resistance, thus leading to type 2 diabetes.

Common Reasons for Disturbed Core Sleep

Several factors can disrupt core sleep:

• Sleep Disorders: Conditions like insomnia and sleep apnea can fragment sleep architecture, reducing the duration of SWS.
• Lifestyle Factors: Irregular sleep schedules, excessive caffeine or alcohol intake, and high levels of stress can negatively impact sleep quality.
• Medical Conditions: Chronic illnesses, including diabetes and cardiovascular diseases, can interfere with sleep patterns. For example, high blood sugar can disrupt your sleep by increasing the number of visits to the toilet.

Health Consequences of Poor Core Sleep

Inadequate core sleep has been linked to various health issues:

• Metabolic Dysregulation: Poor sleep can impair glucose metabolism and insulin sensitivity, increasing the risk of type 2 diabetes.
• Obesity: Disrupted sleep affects hormones that regulate appetite, leading to increased hunger and potential weight gain.
• Cardiovascular Diseases: Chronic sleep deprivation is associated with hypertension and other heart-related conditions.

Continuous Glucose Monitoring helps in lowering A1C levels. The continuous monitoring has been made possible with the help of continuous glucose monitors, commonly known as CGMs. Everything you want to know about CGMs.

Different Types of Sleep and Their Significance

Sleep is categorized into two main types:

Non-Rapid Eye Movement (NREM) Sleep:

• Stage 1 (N1): This is the lightest sleep stage, serving as the transition from wakefulness to sleep. It lasts approximately 10 minutes and is characterized by a decrease in muscle activity and slow eye movements.
• Stage 2 (N2): Representing light sleep, this stage involves further slowing of heart rate and a drop in body temperature. Brain activity shows sleep spindles and K-complexes, which are thought to protect sleep and aid memory consolidation.
• Stage 3 (N3): Also known as deep sleep or slow-wave sleep (SWS), this stage is crucial for physical restoration, growth, and immune system strengthening. It is characterized by delta waves—slow, high-amplitude brain waves.

Rapid Eye Movement (REM) Sleep:

This stage is associated with vivid dreaming and increased brain activity, similar to wakefulness. REM sleep plays a vital role in cognitive functions such as memory consolidation, learning, and mood regulation.

Core Sleep and Its Timing

Core sleep primarily refers to the deep sleep phase (N3), which is essential for restorative processes. A typical sleep cycle lasts about 90 minutes and includes all stages of NREM and REM sleep. Deep sleep usually occurs within the first one or two cycles, approximately 20 to 40 minutes after falling asleep. As the night progresses, the duration of deep sleep decreases, while REM sleep periods become longer.

Sequence of Sleep Stages

The progression through the sleep stages follows this pattern:

Stage 1 (N1): Transition from wakefulness to sleep.

Stage 2 (N2): Light sleep.

Stage 3 (N3): Deep sleep (core sleep).

Stage 2 (N2): Light sleep.

Stage 5 (REM): REM sleep.

This cycle repeats throughout the night, with each complete cycle lasting about 90 minutes. The proportion of time spent in each stage varies, with more deep sleep occurring in the earlier part of the night and longer REM periods towards the morning.

• Sleep Stages Covered by Power Naps: In order to avoid sleep inertia—a feeling of grogginess upon waking—power naps usually attempt to incorporate Stage 2 of NREM sleep, avoiding deeper levels. These little (10–20 minute) naps can improve performance and alertness without disrupting sleep at night. verywellhealth.com Do Power Naps Have Health Benefits? The Best Time to Take Power Naps Indeed power naps have a number of health advantages.
• Increased Alertness: Quick naps can lessen weariness and enhance cognitive function.
• Enhanced Mood: Napping can alleviate stress and improve mood.
• Cardiovascular Benefits: Regular napping has been linked to a reduced risk of heart disease.

The optimal time for a power nap is early afternoon, typically between 1:00 PM and 3:00 PM, aligning with the body’s natural circadian dip in alertness.

Does Diabetes Affect Core Sleep?

Yes, diabetes can adversely affect core sleep:

• Peripheral Neuropathy: Caused by high blood sugar levels, this nerve pain can lead to discomfort during sleep.
• Nocturia: Frequent urination is a common sign of diabetes. Needing to pee during the 6 or 8 bed hours can disrupt sleep continuity.
• Restless Leg Syndrome: Common in diabetics, leading to difficulty falling and staying asleep.

Addressing these issues is crucial, as poor sleep can further impair glucose metabolism, creating a vicious cycle.

Conclusion:

Along with the consequences of disturbed core sleep, this blog answers the common question, ‘What is core sleep?’ Core sleep is the stage of sleep that is vital for our physical and mental health. One sleep cycle takes approximately 90 to 110 minutes. Usually completed during the first 3 cycles of sleep, core sleep primarily refers to the deepest stage of sleep, which is also known as slow wave sleep (typically stages 3 and 4 of non-REM sleep) and is considered the most restorative part of the sleep cycle.