Reset Your Sleep With The Master Sleep Hormone
What is Melatonin
Melatonin is a hormone made by the pineal gland, a pea sized gland located just above the middle of the brain. It is most well-known for its role in maintaining the body’s sleep-wake cycle, also known as the circadian rhythm. Apart from the brain, melatonin receptors are also found throughout the body in places such as the eye, cardiovascular system, liver and gallbladder, colon, skin, kidney and many others. Lesser known functions of melatonin include regulation of blood pressure, immune function and cortisol levels. It is also a potent antioxidant and has also been associated with improved mood, neurogenesis and neuroprotection. Because melatonin receptors can be found throughout the body, melatonin has also been found to support eye health, improve certain gastrointestinal conditions and reduce symptoms of tinnitus.
How does Melatonin work?
When the sun goes down and darkness occurs, the pineal is “turned on” and begins to actively produce melatonin, which is released into the blood. As a result, melatonin levels in the blood rise sharply and you begin to feel less alert. Your body temperature lowers and sleep becomes more inviting. It also binds to receptors in the body and can help you relax. For instance, melatonin binds to receptors in the brain to help reduce nerve activity. In the eyes, it can help reduce dopamine levels, a hormone that helps you stay awake. There are many factors that may cause low levels at night. Stress, smoking, exposure to too much light at night, including blue light, not getting enough natural light during the day, shift work and aging all affect melatonin production.
Melatonin levels in the blood stay elevated for about 12 hours – all through the night – before the light of a new day when they fall back to low daytime levels. Daytime levels of melatonin are barely detectable.
In addition to its circadian rhythm, melatonin levels also have a seasonal rhythm, with higher levels in the autumn and winter, when nights are longer, and lower levels in the spring and summer.
What is the appropriate dosage to be taken?
For melatonin to be helpful, the correct dosage, method and time of day it is taken must be appropriate to the individual’s need. Taking it at an inappropriate time and dosage may reset your biological clock in an undesirable direction. How much to take, when to take it, and melatonin’s effectiveness, is only beginning to be understood.
There are large variations in the amount of melatonin produced by individuals, depending on age, lifestyle and environmental factors and these are not associated with any health problems. The main consequences of swallowing large amounts of melatonin are drowsiness and reduced core body temperature. Very large doses have effects on the human reproductive system. In a study done by MIT researchers, it was found that the physiological dose of melatonin of about 0.3 milligrams restores sleep in adults over the age of 50.
Melatonin supplements are typically sold in tablets of 1, 3, 5 and 10 mg, the right amount depends on your individual situation and how your body processes the supplement. It is recommended to start with smaller doses of 0.3mg, gradually increasing or decreasing your dosage until you find the right amount. If you have trouble falling asleep or staying asleep, you may consider increasing the dose. Feeling groggy the next morning after experiencing a full night sleep, experiencing vivid dreams and/or headaches are some signs that you might want to consider decreasing your dose. Taking melatonin in a form that allows for precise titration is thus a better option for most people as their melatonin needs can vary from day to day.
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Dr Deborah Wong
Dr Deborah Wong obtained her MBBS from the National University of Singapore and post graduate training in Family Medicine with the College of Family Physicians Singapore. She has a special interest in preventive health, women’s health and sports medicine. She has also undergone training and attained various certifications in exercise medicine and Clinical Orthopedic Manual Therapy.
She believes that healthcare should be holistic, and treatment should involve mind, body and soul. She is currently pursuing integrative and functional medicine training with the Australasian College of Nutrition and Environmental Medicine to complement her practice.