Why Sleep Is Essential for Your Health

BY AISHWARYA ATMAJA

Have you ever stayed up late scrolling through your phone, only to feel grumpy and unfocused the next day?

Good sleep does more than help you feel rested. It supports your brain, boosts your mood, strengthens your immunity and protects your heart. Sleep health is as vital as nutrition and exercise for overall well-being. In this article, we’ll explain why sleep matters, what can go wrong when you don’t get enough, how much sleep you might need and how to build better sleep habits.

How Sleep Supports Your Body and Mind

Sleep is not just downtime. Deep sleep releases growth hormones and repairs tired muscles and tissues. It also strengthens your immune system, helping your body fight off illness and recover more quickly when you get sick. Consistent quality sleep supports emotional balance, memory, concentration, and decision-making abilities.

Sleep and mental health are closely linked, as consistent, restorative sleep helps regulate mood, reduce stress and lower the risk of developing depression. This means that poor sleep can contribute to the development of depression, and having depression makes a person more likely to experience sleep troubles, such as insomnia, hypersomnia and obstructive sleep apnea.

Poor sleep, especially at night, can sometimes cause growth problems, particularly in children. Some children with untreated sleep disorders have a higher risk of stunted growth. This is because the release of growth hormone will be slower than usual. During deep sleep, especially in the early part of the night, your brain releases large amounts of growth hormone, which helps repair tissues and supports healthy development in children and teens.

Short-Term Effects of Sleep Loss

• Even one night of poor sleep can leave you feeling tired, forgetful, and irritable. You may struggle to focus, react more slowly and find it harder to solve problems. Your immune system becomes less effective, increasing your chances of catching a cold or influenza (flu).

• Even one night of poor sleep can lead to noticeable physical symptoms. Sleep deprivation causes dark under-eye circles, drooping eyelids, and paler skin tone — all common signs of tiredness that can show up quickly.

A study published in the journal Sleep found that people who missed sleep appeared visibly less healthy and more fatigued, with puffier eyes and duller skin. These physical changes happen because the body isn’t given enough time to repair and restore itself during rest. Sleep-deprived individuals may also experience slower reflexes, body aches and poor coordination, making everyday tasks like walking, writing or concentrating feel harder than usual. Headaches and sensitivity to light are also frequently reported after just one bad night. These short-term physical effects serve as the body’s way of signaling that it needs rest and ignoring those signs can lead to bigger health problems if the cycle continues.

Long-Term Risks of Poor Sleep

Chronic lack of sleep or inconsistent sleep patterns raises the risk of serious health problems. People who routinely sleep fewer than seven hours a night face higher odds of heart disease, stroke, high blood pressure and type 2 diabetes. Hormonal shifts from inadequate sleep can reduce insulin sensitivity and disrupt metabolism, increasing the chances of obesity and overweight over time.

Irregular sleep timing — such as going to bed late or varying bedtime each night — has been linked to even higher risks.

Studies show irregular sleep schedules may increase the likelihood of developing dozens of conditions, including liver disease, diabetes, Parkinson’s disease and kidney failure. One recent summary of research from the UK Biobank estimated that inconsistent sleep patterns contributed to as many as 172 chronic diseases. Another study found irregular bedtimes raised heart attack and stroke risk by 26 percent, even among people who got seven to eight hours of sleep. Quality sleep habits have also been shown to contribute to longevity. Adults who sleep well— seven or eight hours a night, wake up feeling rested and maintain regular sleep schedules—may live two to five years longer.

How Much Sleep Do You Need?

Recommended daily sleep varies by age:

• Teenagers (13–18): eight to 10 hours

• Adults (18 and older): seven to nine hours

• School-age children (6–12): nine to 12 hours

• Younger children and infants: more than 12 hours

These are general guidelines. Some individuals may require more or slightly less, depending on their genetics, health status, or life stage.

Tips for Better Sleep

Here are practical ways to improve your sleep:

1. Keep a consistent sleep schedule. Wake up and go to bed at the same time every day, even on weekends.

2. Create a restful bedroom. Keep the room cool, quiet and dark. Avoid screens for at least 30 minutes before going to bed.

3. Limit caffeine and heavy meals late. Avoid coffee or energy drinks in the afternoon.

4. Stay active during the day. Regular exercise supports better sleep, but avoid intense activity right before bed.

How to Avoid “I’ll Sleep Later” Mistakes

It’s tempting to skip sleep when deadlines or social activities are pressing. But sleep debt, the buildup of missed sleep over time, is difficult to fully recover from and can quickly affect both mental and physical health.

Even short-term sleep loss can lead to mood swings, memory trouble, reduced alertness and weakened immune responses. According to the Centers for Disease Control and Prevention, missing sleep during the week and attempting to “catch up” on the weekend does not reverse the impact on your brain and body. The Sleep Foundation also explains that inconsistent sleep patterns can confuse your internal clock, making it harder to fall asleep when you need to. Instead of relying on weekend recovery sleep, it is better to create consistent bedtime habits throughout the week.

You can start by finishing schoolwork or chores earlier in the evening, limiting screen time and keeping your room dark and quiet before bed. People often consider sleep like it’s a reward, but in fact, it’s not. Treating sleep as something optional or to be “earned” after work or school sets up a dangerous mindset. Going to bed at the same time each night supports better long-term health.

When sleep becomes an afterthought, it’s easy to fall into poor habits — scrolling late into the night, staying up for tasks that could wait or skipping rest altogether. Instead, plan your day so that sleep is part of your schedule, not squeezed into it. Create a regular bedtime and stick to it, even on weekends. By making sleep a non-negotiable part of your routine, you’re choosing to protect your well-being every day, not just when everything else is done. Make sleep a priority, not a reward.

Conclusion

Sleep isn’t optional — it is essential. It restores your brain, strengthens your body, balances your mood and helps prevent chronic illness. By aiming for proper hours, keeping a regular schedule and creating a peaceful bedtime routine, you give yourself a powerful tool for health and longevity.

Tonight, turn off the lights, unplug your screens and let your body do the important work of rest.

Credits and Resources

• National Institutes of Health (NIH) – Good Sleep for Good Health: https://newsinhealth.nih.gov/2021/04/good-sleep-good-health

• Harvard Division of Sleep Medicine – Sleep and Health: https://sleep.hms.harvard.edu/education-training/public-education/sleep-and-healtheducation-program/sleep-health-education-86

• Sleep Foundation – Why Do We Need Sleep?: https://www.sleepfoundation.org/howsleep-works/why-do-we-need-sleep

• American Heart Association (AHA) – Lack of Sleep and Heart Disease: https://www.heart.org/en/healthy-living/healthy-lifestyle/sleep/lack-of-sleep-and-heartdisease

• Times of India – Irregular Sleep May Raise Risk of 172 Diseases: https://timesofindia.indiatimes.com/life-style/health-fitness/health-news/irregular-sleepmay-raise-risk-of-172-diseasesincluding-diabetes-and-kidneyfailure/articleshow/123040815.cms

• New York Post – Hidden Sleep Danger Could Increase Risk of 172 Diseases: https://nypost.com/2025/07/31/health/hidden-sleep-danger-could-increase-risk-of-172- diseases/

• The Sun – Late Bedtime Linked to 172 Diseases: https://www.thesun.co.uk/health/36076579/gangrene-liver-damage-diabetes-conditionslate-bedtime/

• Tom’s Guide – 5 Sleep Habits for Longevity: https://www.tomsguide.com/wellness/sleep/i-asked-a-longevity-expert-how-to-livelonger-these-are-the-5-sleep-habits-he-swears-by

• Cleveland Clinic – Sleep Basics: https://my.clevelandclinic.org/health/body/12148-sleepbasics

• Wikipedia – Sleep Deprivation: https://en.wikipedia.org/wiki/Sleep_deprivation

• Wikipedia – Sleep and Metabolism: https://en.wikipedia.org/wiki/Sleep_and_metabolism • Sleep Foundation – Depression and Sleep: https://www.sleepfoundation.org/mentalhealth/depression-and-sleep

• The Verywell Health – How to Get More Deep Sleep: https://www.verywellhealth.com/lack-of-deep-sleep-3966027