The importance of sound sleep

Mridula Wattas

All human beings as well as plants and animals operate within a 24-hour cycle called the circadian rhythm, also known as sleep/wake cycle. This cycle is influenced by day light and environmental temperature. Circadian rhythms are important in determining the sleeping and feeding patterns of all living beings. All biological activities like hormone production and cell regeneration are linked with this daily cycle. 

For most adults, the biggest dip in energy happens in the middle of the night (somewhere between 2 am and 4 am and just after lunchtime (around 1 pm to 3 pm, when they tend to crave a post-lunch nap). However, for night owls or a morning persons, this can happen according to their indiviual cycle. It is important to be aware of your normal body rhythm. You should adjust your eating pattern and work schedule accordingly for good health and sound sleep.

Significance of sleep

For repair and restoration of the body

The growth hormone, essential for the repair and restoration processes of the body, is secreted during sleep. This is a natural repair mechanism of the body which happens while we are sleeping. Another hormone secreted during sleep is the testosterone, the male hormone. So fitness aficionados should keep in mind that at least 6-7 hours sleep is as essential for muscle building as are cardio and muscle building exercises and diet.

For maintaining healthy weight

Poor sleep can lead to weight gain. People who do not get a good night’s sleep always feel that they are low in energy and so are unable to follow any exercise regime during the day. Sleep deprivation disrupts the daily fluctuations in appetite hormones and is believed to disrupt appetite regulation. The feeling of low energy also leads to making wrong food choices, like foods rich in fats and sugar. In absence of any physical activity and increased calorie intake weight gain happens.

For protection against heart disease, 

diabetes and auto-immune disorders  

Loss of sleep can prompt one’s immune system to turn against healthy tissue and organs leading to tissue-damaging inflammation which is what happens in the auto immune diseases.

Inadequate or poor quality sleep also causes levels of the stress hormone cortisol to rise. High cortisol levels and systemic inflammation can trigger or worsen insulin resistance which leads to diabetes and heart disease. Prolonged sleep loss can also lead to elevated blood pressure.

Melatonin – the sleep hormone

Melatonin is a hormone produced in the pineal gland of the brain that is responsible for regulating sleep cycles. Melatonin is produced during the night time, two hours before a person goes to sleep. For a good sleep at night it is important to ensure adequate melatonin production in the body. The following steps can help the body to produce melatonin:

• Regular physical exercise during day and adequate exposure to sunlight helps to regulate the circadian rhythm of the body. Thus it can help in producing high level of melatonin at night. So exercise should be a part of your daily routine. 
• Melatonin production is increased by darkness so darken your bedroom before sleeping. 
• Avoid eating any food three hours before bed, as this will optimise your blood sugar, insulin and leptin levels and contribute to overall good health and a restful sleep.  
• Avoid drinks like coffee and alcohol during late evening and at bedtime as these act as stimulants and may lead to loss of sleep.
• Avoid highly spicy foods and fried and heavy meals at dinner as this may lead to indigestion and restless sleep. 

Foods that can boost sleep

• Some foods naturally contain melatonin boosting properties. So one should include these during dinner time or eat them as a bed-time snack. 

Sweet potato and bananas: These provide sleep-promoting complex carbohydrates which boost melatonin production. These foods also contain potassium which relaxes the muscles and induces sleep.

Cherry juice: According to researchers from the Universities of Pennsylvania, a glass of cherry juice causes an improvement in the melatonin level leading to better sleep.

Other foods that boost melatonin production are sweet corns, pineapple, rice and barley.

• Certain foods contain the amino acid tryptophan which increases serotonin levels in the brain leading to higher melatonin production. These foods are: 
• Nuts like almonds and walnuts 
• Dairy products like cheese and milk
• Pulses like chickpeas
• Poultry like turkey and chicken
• Natural sugar like honey helps in easy entry of tryptophan into the brain.

BOTTOMLINE

A healthy balanced diet, a moderate exercise schedule, a regular sleeping pattern with the addition of some sleep-enhancing foods at bed time is your best bet for a good night’s sleep. Considering the importance of sound sleep in maintaining good health, it is surely worth a try.

—The writer is former head, Department of Dietetics, PGIMER, Chandigarh