Tonight, Good Sleep: Sleep Common Sense You Should Know
This book by Seiji Nishino shares sleep insights, emphasizing its importance for immunity, weight management, and overall health. Learn practical tips to improve sleep quality and combat sleep disorders.
What you'll gain:
- Boost your immune system through improved sleep.
- Achieve better weight management by understanding the link between sleep and hormones.
- Learn to identify and address common sleep disorders.
Core Content:
1. Sleep is Fundamental for Preventing Infectious Diseases
- Sleep deprivation weakens the immune system.
- Adequate sleep enhances resistance to bacteria and viruses, boosting innate immunity.
- If infected, sufficient sleep aids in the antibody production of adaptive immunity, accelerating recovery.
- Sleep deprivation can weaken the effectiveness of vaccines.
2. Sleep Deprivation Leads to Weight Gain
- Hormone imbalances due to lack of sleep alter appetite.
- Sleep deprivation reduces leptin (appetite suppressor) and increases ghrelin (appetite stimulant).
- Insufficient sleep also reduces daytime activity levels, contributing to weight gain.
3. "90-Minute Multiples" for Sleep Are Not Always Best
- Sleep cycles vary; individual differences and physical condition disrupt sleep patterns.
- Sleep cycles (NREM to REM sleep) typically last about 90 minutes but can range from 80 to 120 minutes.
- Sticking to 90-minute multiples doesn't guarantee effective waking, as the sleep cycle might be disturbed by sleep debt or circadian rhythm issues.
4. The Importance of the First 90 Minutes
- The initial NREM sleep cycle (the "Golden 90 Minutes") is crucial for sleep quality.
- Good quality sleep in this period ensures better sleep throughout the night.
- Growth hormone secretion is most active during this phase, critical for overall health.
5. Light Exposure Can Reset the Biological Clock
- The biological clock, located in the brain's hypothalamus, sends instructions to the "clock genes" throughout the body.
- Morning sunlight effectively corrects deviations in this clock.
6. Alcohol Should be Moderated
- In small doses, alcohol calms brain activity, promoting sleep.
- However, excessive alcohol alters natural deep sleep and REM sleep patterns.
- It also acts as a diuretic, disrupting sleep with frequent awakenings and potential dehydration.
Q&A
Q: How does sleep affect immunity?
A: Adequate sleep strengthens the immune system by improving the function of innate immunity (the body's first line of defense) and enhancing the antibody response of adaptive immunity when infected.
Q: Why does sleep deprivation lead to weight gain?
A: Sleep deprivation disrupts hormone balance, reducing leptin (which suppresses appetite) and increasing ghrelin (which stimulates appetite), leading to overeating and reduced physical activity.
Q: Why are the first 90 minutes of sleep so important?
A: The initial NREM sleep phase, known as the "Golden 90 Minutes," is vital for hormone regulation, deep relaxation, and setting the stage for quality sleep throughout the night.
Q: What are the effects of shift work on sleep?
A: Shift work disrupts the body's natural circadian rhythm. It increases health risks such as obesity, diabetes, and mental health issues like depression.
