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Ecological Medicine - Australian

Voice Over • Audiobooks


An excerpt from the non-fiction book written by Sarah Myhill.

Vocal Characteristics


English (Australian)

Voice Age

Young Adult (18-35)




Note: Transcripts are generated using speech recognition software and may contain errors.
went to sleep. Circadian rhythm. Humans evolved to sleep when it is dark and wake when it is light. Sleep is a form of hibernation when the body shuts down in order to repair damage done through use to conserve energy and to hide from predators. The normal sleep pattern that evolved in hot climates is to sleep. Keep warm and conserve energy during the cold nights and then sleep again in the afternoons when it is too hot to work and to hide away from the mid day sun as humans migrated away from the equator. This sleep pattern had to change with the seasons, and as the length of the day has changed in winter, we need to shut down to conserve energy. This means more sleep. Mild fatigue and depression in winter prevent us from spending energy unnecessarily. Conversely, in the summer we need to expand large amounts of energy to harvest the summer bounties and accumulate reserves to carry us through the winter. We naturally need less sleep, can work longer hours and have more energy. But the need for arrest, if not asleep in the middle of the day, is still there. Therefore, it is no surprise that young Children, the elderly and people who become ill often have an extra sleep in the afternoon. And for these people, that is totally desirable. Others have learned to power nap as it is called during the day, and this allows them to feel more energetic later. If you can do it, then this is an excellent habit to get into. It can be learned. The average daily sleep requirement is nine hours, ideally taken between 9:30 p.m. And 6 30 AM That is during the hours of darkness, but allow for more in the winter and less than a summer. An hour of sleep before midnight is worth two after. This is because human growth hormone is produced during the hours of sleep before midnight. The symptom of jet lag is a powerful illustration of the existence of a circadian rhythm. Circadian rhythms start with light, which impacts on the skin interestingly, not necessarily through the eyes, and switches off melatonin production. As darkness ensues, melatonin is produced to create the hormonal environment for sleep. Melatonin stimulates the pituitary gland to produce thyroid stimulating hormones, and this peaks at midnight. The thyroid is stimulated to produce T four thyroid oxen, which spikes at four AM This is converted to the active thyroid hormone T three, which spikes at five AM t three kicks the adrenals into life and the rising levels of adrenaline, cortisol and dhe a wake us up at 6 to 7 a.m. My guess is that it is the varying levels of all these hormones throughout the night that determines the proportion of non REM to REM sleep. And this, too, is critical for good health. Good thyroid and adrenal function are essential for good quality sleep.