By Lisa Paradiso, RD, LD
Everyone can recall the feeling of waking up after a good night’s sleep. Feeling rested elicits a sense of energy and readiness to take on the day. Conversely, waking up after a poor night’s sleep can make a person feel foggy and heavy-eyed for the remainder of the day. It is important to get a good night’s sleep not only to prevent the groggy feeling a poor night’s sleep provides, but also for a myriad of other physiological reasons as well. During the deep stages of sleep, your body is busy working to restore hormones, replenish neurotransmitters, and maintain overall homeostasis, or balance, in the body.
Adults require seven to eight hours of sleep each night to maintain overall health and without adequate sleep can be at an increased risk of multiple health problems. Diminished sleep affects appetite, the body’s immune response, concentration, learning, memory, metabolism, sedentary behaviors, and can increase a person’s risk for heart disease and diabetes. The average American sleeps six hours and thirty minutes each night, putting about fifty percent of Americans at a deficit.
How We Sleep
Sleep is broken down into 5 stages in which the body undergoes different chemical reactions. All 5 stages take about 90 minutes to complete, and a person goes through these stages several times in one night. If awakened during a particularly deep stage of sleep, one will likely experience feelings of grogginess or being out of focus. In the first stage of sleep, eyes become heavy and restfulness starts to set in; sleep is fragmented and shallow. Stage 2 is the longest stage of sleep where heart rate begins to slow and sleep is light. Stage 3 and 4 are the deepest stages of sleep where the body begins repairing injuries, synchronizing organ systems, replenishing neurotransmitters, and restoring hormones that you will use throughout the day. Some of the neurotransmitters restored are responsible for memory, alertness, and happiness. The hormones synthesized are also responsible for growth of muscle tissue, endurance, and regulation of body systems. Stage 5 is REM (rapid eye movement). This is the stage where dreaming occurs, but also when memories from the day are consolidated, creativity is enhanced, and efficiency for the day is improved. The length of this stage increases as morning approaches, and without this stage it would be difficult to recall information learned in the past.
How Sleep Influences Our Health
Sleep habits can influence health in many ways. A person’s appetite, physical activity, meal choices, and medical conditions can be affected when sleep is disturbed or shortened. Additionally, lack of sleep is shown to decrease a person’s ability to acquire new information, consolidate it, and recall the information at a later time.
In the short term, diminished sleep can affect mood, judgement, efficiency, productivity, and appetite. It can disrupt a person’s ability to focus attention and learn new things. Lack of sleep can impact cravings, satiety, hunger and energy due to increased need for energy by the central nervous system. When the brain requires more energy to work efficiently, it increases cravings for high fat, high sugar foods to account for energy deprivation. Decreased sleep has also been shown to affect the hormones responsible for hunger and fullness. When you receive six hours of sleep or less (even for just one night)ghrelin, the hormone responsible for making you feel hungry is increased and leptin, the hormone responsible for satiety is decreased.
Chronic loss of sleep is also attributed to increased risk for anxiety, obesity, depression, diabetes, high blood pressure, elevated blood sugars, cardiovascular disease, and other diseases. Interestingly, these conditions are also associated with too much sleep (more than 9 hours of sleep in one night). This demonstrates how a poor balance of sleep alters the metabolism and hormone production enough to cause short-term and long-term damage to the body.
Adequate sleep is vital for healing, repairing, and replenishing body tissues. When focusing on optimal health and overall well-being, it is important to prioritize sleep in addition to other self-care behaviors. To ensure ideal rest, aim for seven to eight hours of good quality sleep each night!
Tips for a Better Night’s Sleep
- Allow at least 7.5 hours of time in bed to ensure you are able to sleep for the adequate duration
- Avoid skipping meals or going to bed hungry to limit nighttime cravings
- Limit caffeine containing foods within 6 hours of bedtime
- Avoid excessive fluid intake close to bedtime
- Avoid late day naps exceeding 20 minutes
- Avoid exercising within 2 hours of bedtime
- Set an alarm for 8 hours after getting into bed to avoid over-sleeping past 9 hours
- Turn off electronics within an hour of bed or switch to nighttime mode
- Avoid high fat meals before bed
- Keep your bedroom cool
- Avoid alcohol before bed which can reduce length of REM sleep and arouse the brain pre-maturely
- Avoid watching television close to bedtime or as you fall asleep. Calming music or pink/white noise is more effective in helping you fall asleep
- Make your bedroom an inviting, peaceful place
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