A good night’s sleep is just as important as regular exercise and a healthy diet. Sleep is an important part of our daily routine—we spend about one-third of your time doing it. Quality sleep – and getting enough of it at the right times -- is as essential to survival as food and water. How you feel during the day partly depends on how well you sleep at night. The first signs of inadequate sleep include feeling irritated, forgetful, and fatigued etc.
Sleep is the balm that soothes and restores after a long day. Sleep is important to a number of brain functions, including how nerve cells (neurons) communicate with each other. In fact, your brain and body stay remarkably active while you sleep. Recent findings suggest that sleep plays a housekeeping role that removes toxins in your brain that build up while you are awake.
Sleep is largely driven by the body’s internal clock, which takes cues from external elements such as sunlight and temperature. The body’s natural sleep-and-wake cycle is reasonably attuned to a 24-hour period.
What Is a Good Night’s Sleep?
A good night’s sleep should leave you feeling refreshed, alert, and ready to begin the day. If you happen to wake from a deep sleep, you may need a few minutes to wake up properly. But overall, people with healthy sleep patterns find it easy to fall asleep and experience minimal nighttime awakenings.
Quality sleep is not just about the hours you spend in bed. Fragmented sleep can also disrupt the natural rhythm of the sleep stages, leading to a less productive rest. You may get exactly eight hours of sleep every night and still feel groggy as a result of light or restless sleep. If you’re experiencing any of the following symptoms, you might not be getting the rest you need:
Difficulty waking up or falling asleep
Not feeling well-rested when you wake up
Feeling tired, sleepy, or drowsy during the day
Reduced performance or trouble focusing at school, work, or sports
Excessive reliance on caffeine
Frequent nighttime awakenings
Subjective feelings of not sleeping well
Why the Brain Needs Sleep
Sleep is something the brain needs. Our brains run on electricity, which means the chemical energy the brain uses to function has waste products (called metabolites) that need to get cleaned out. That’s what happens during sleep. The brain flushes out that waste during sleep. The brain also experiences a spike in adenosine triphosphate (ATP), a molecule the brain uses for energy and that’s essential for communication between brain cells.
You likely won’t be measuring your daily ATP levels, but they do affect your ability to function in big ways.
If you don’t get a good night’s sleep and those chemical processes don’t happen, the next day you’ll likely notice:
It’s tougher to concentrate.
It’s harder to remember things.
You’re moody and irritable.
Your judgment might be skewed.
You have less patience.
You’re more likely to make rash decisions or have a tough time making decisions.
You’re more emotional than usual.
Your hand-eye coordination is a little bit off.
How you feel during the day partly depends on how well you sleep at night. The first signs of inadequate sleep include feeling irritated, forgetful, and fatigued, according to the American Sleep Association. You may also experience mental health issues and a decreased ability to perform your job successfully.
Sleep deprivation may cause “mood changes such as easy irritability and overreacting to common stressors, having fluctuating emotions, and feeling anxious or depressed.
Why the Body Needs Sleep
Of course, it’s not just our minds that need sleep. Other systems of the body don’t work quite right when they’re too tired, either. Immediately after a poor night’s sleep you might notice you are hungrier and tend to crave and eat more, and people are also at higher risk of catching a cold or flu. It's because sleep deprivation has been shown to mess with how the immune system functions.
Over time, chronic poor sleep has been linked to worse heart health. So much evidence points to this that the American Heart Association updated its checklist of modifiable factors linked to cardiovascular health in June 2022 to include sleep. The list also includes diet, exercise, tobacco use, weight, cholesterol, blood sugar levels, and blood pressure, and is published in the journal Circulation.
Sleeping poorly over time has also been shown to increase the risk of:
Obesity
Type 2 diabetes
Heart disease and hypertension
Depression, anxiety, and other mood disorders
Poor immune function
Earlier death
How Much Sleep Do I Need?
Sleep needs differ from person to person and across different age groups. One person may need eight full hours, while another can function with less sleep. Sleep needs vary by age, and variation exists even within age groups.
But in general, The National Sleep Foundation provides these daily sleep guidelines:
Infants (4-11 months): 12-15 hours
School-age children (6-13): 9-11 hours
Teenagers (14-17): 8-10 hours
Young adults (18-25): 7-9 hours
Adults (26-64): 7-9 hours
Older adults (65+): 7-8 hours
The Different Stages of Sleep
During sleep the brain cycles, repeatedly, through different stages.
Stage 1: Non-REM (rapid eye movement) sleep The first stage is when you’re falling asleep — stage 1 non-REM. Your heartbeat, breathing, and eye movement start to slow down, and your muscles relax. Your brain waves also slow down, and it’s still very easy to wake up during this preliminary stage of sleep.
Stage 2: Non-REM sleep In the second stage, your heart rate drops and your body temperature falls even more. Eye movement stops completely and your brain slows way down, except for brief bursts of activity.
Stage 3: Non-REM sleep Next comes deep sleep. This stage is heavy and restorative. Your heartbeat and breathing slow down the most during this type of sleep, and now is the time when it's hardest to awake.
REM sleep Finally comes REM sleep, when your eyes begin to dart quickly back and forth from side to side (even though your eyelids are still closed). Brain activity speeds way up, closer to the amount of activity that happens when you’re awake. This is the stage of sleep when most of your dreaming happens. Your breathing speeds up and becomes irregular during REM sleep. Heart rate and blood pressure start to climb back to waking levels, but the muscles of your arms and legs become temporarily paralyzed. Sleep experts suspect this paralysis is a mechanism our bodies developed to protect us from injury or other harm that might otherwise ensue if we were to “act out” our dreams.
Each cycle of sleep (a set of all the stages) usually takes about 90 minutes. And most people tend to spend more time during each cycle in deeper sleep earlier in the night — and more time in REM sleep later on. Each stage of sleep is important, and both deep sleep and REM sleep play critical roles in the learning and memory consolidation processes that happen during sleep.
How Can I Get A Better Night’s Sleep?
Sleeping well directly affects our mental and physical health. Fall short and it can take a serious toll on our daytime energy, productivity, emotional balance, and even our weight. Yet many of us regularly toss and turn at night, struggling to get the sleep we need.
Good sleep habits (sometimes referred to as “sleep hygiene”) can help you get a good night’s sleep.
Here are some habits that can improve your sleep health:
Be consistent. Go to bed at the same time each night and get up at the same time each morning, including on the weekends
Make sure your bedroom is quiet, dark, relaxing, and at a comfortable temperature.
Remove electronic devices, such as TVs, computers, and smart phones, from the bedroom
Avoid large meals, caffeine, and alcohol before bedtime
Get some exercise. Being physically active during the day can help you fall asleep more easily at night.
Relax before bed – try a warm bath, reading, or another relaxing routine.
Here are some foods and drinks we can have before bed to enhance our quality of sleep.
Also, avoid sleeping in—even on weekends. The more your weekend/weekday sleep schedules differ, the worse the jetlag-like symptoms you’ll experience. If you need to make up for a late night, opt for a daytime nap rather than sleeping in. This allows you to pay off your sleep debt without disturbing your natural sleep-wake rhythm.
Bottom Line
Sleep plays a key role in our health. Insufficient sleep has been linked to an increased risk of obesity by 89% in children and 55% in adults. Other studies conclude that getting less than 7–8 hours per night increases your risk of developing heart disease and type 2 diabetes.
So, let's keep in sync with our body’s natural sleep-wake cycle, exercise during the day, be smart about what we eat and drink and improve your sleep environment. Our mind and body (and our family!) will thank us for it.
About the authors:
Madur & Anitha Jagannath are certified Nutrition Consultants, in addition to their professions in technology and human resources. When Madur started feeling lethargic and slowing down, he started exercising regularly, became conscious of healthy eating habits and nutrition. He is an avid runner and does half-marathons often. At Voyage to Wellness, they attribute our reputation to the lasting customer relationships they have developed throughout the years. They believe in health & wellness and being fit, at all stages of people's lives.
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