Former Director Grade Scientist, Centre for Cellular and Molecular Biology, Hyderabad, India
www.daylife.page
The Earth's rotation creates the diurnal cycle of light and darkness, temperature and humidity changes. The Earth's rotation causes tides in the oceans and seas. These celestial events regulate our biological clock. This clock gives us the sense of time and controls circadian rhythms. A circadian rhythm, is a natural cycle repeats roughly every 24 hours. Circadian rhythms can refer to any process that originates within an organism and responds to the environment. This internal clock is made up of proteins encoded by thousands of genes. The master clock is located in the suprachiasmatic nucleus (SCN), a group of nerve cells in the hypothalamus. The SCN is sensitive to light, which influences the signals it uses to coordinate circadian rhythms (Gupta, P.D. and Pushkala, K. Clocks within us (2012), LAMBERT Academic Publishing, Germany)
The circadian rhythm controls many activities in the body, including:
• Sleep-wake cycle: The circadian rhythm regulates sleepiness and alertness in response to light changes.
• Hormones: The circadian rhythm controls hormone release.
• Appetite and digestion: The circadian rhythm influences appetite and digestion.
• Temperature: The circadian rhythm controls body temperature.
• Heart rate: The circadian rhythm influences heart rate.
• Blood pressure: The circadian rhythm influences blood pressure.
• Urine production: The circadian rhythm influences urine production.
• Energy expenditure: The circadian rhythm helps optimize energy expenditure.
Not only “You are what you eat”, but a growing body of evidence indicates that it's not just what and how much one eats that influence the person’s health. How fast and when one eats also play a crucial role in keeping good health?.
• To help reset circadian cycle, one may establish a daily routine with set activities that happen during the day and another set of activities that happen at night. This may help manage the symptoms of circadian rhythm disorders.
• Keep a regular meal schedule, especially if you are a shift worker or sleep at irregular times of the day or night.
• Start a regular bedtime routine. Sleep in a cool, quiet place and follow a relaxing bedtime routine that limits stress. These practices, along with regular sleep and waking times, can help you fall asleep faster and stay asleep longer.
• Avoid daytime naps, especially in the afternoon. However, shift workers may benefit from a short nap before the start of their shift.
• Get regular physical activity. Your doctor may recommend getting regular physical activity during the daytime and avoiding exercising close to bedtime, which may make it hard to fall asleep.
• Limit caffeine, alcohol, nicotine, and some medicines, especially close to bedtime.
• Manage your exposure to light. Light is the strongest signal in the environment to help reset your sleep-wake cycle. You may need more sunlight during the day and less artificial light at night from TV screens and electronic devices. Artificial light can lower your melatonin levels, making it harder to fall asleep. Light-blocking glasses, screen filters, or smartphone apps can help dim the light from your electronic devices. Dim lighting for a period before bed may also help reduce the symptoms of a circadian rhythm disorder. For shift workers, wearing light-blocking glasses when you are outside during the day may help.
