Melatonin is a hormone secreted from the pineal gland that regulates your sleep and wake cycles. It normally begins to increase during the evening hours and at the nighttime to prepare your body for sleep. Although melatonin is released normally in healthy people, alcoholism may affect melatonin secretion and change the body’s circadian rhythms.
Alcoholism
Alcoholism, defined as four or more drinks daily for women and five or more drinks for men, produces several adverse effects on your body, including depression, cirrhosis of the liver, loss of appetite and rapid heart rate. Its symptoms include being unable to limit alcohol use, drinking alone or in secret and feeling the urge to drink. Alcoholism can also cause problems at work, relationships and home life, according to the Mayo Clinic.
Melatonin Levels
Scientists at the University of Connecticut Health Center investigated the impact of alcohol consumption on nighttime melatonin levels in healthy women. They discovered that subjects who drank three alcoholic beverages at night experienced a 15-percent decrease in melatonin levels, whereas those who drank four or more alcoholic beverages had a 17-percent reduction. The findings were published in the November 2000 issue of “Epidemiology.”
Melatonin Secretion
Melatonin is normally secreted at night and suppressed during the day. However, in alcoholics it might be reversed, according to a study conducted by researchers at the Centre Hospitalier Universitaire in France. Scientists assigned healthy volunteers 256 g of alcohol over a 24-hour period and assessed their melatonin levels. They observed that subjects experienced decreases in melatonin secretion at night but increases during the day. This can disrupt sleep and lead to conditions such as insomnia or sleep deprivation, according to research reported in the July and August 2006 issue of “Alcohol and Alcoholism.”
Melatonin and Growth Hormone
After melatonin is released, it sends a signal to release growth hormone, which helps repair the body during sleep. Researchers at the Centro di Alcologia-Istituto di Clinica Medica Generale e Terapia Medica in Italy studied the impact of melatonin on growth hormone release in alcoholic men. Participants received 12 mg of melatonin or a placebo and then were tested for growth hormone secretion. At the end of the study, which was published in the June 1998 issue of “Neuropeptide,” researchers found that those in the melatonin group didn’t experience a significant change in growth hormone levels compared with those who had a placebo. This suggests that alcoholism prevents melatonin from releasing growth hormone.
References
- Mayo Clinic; Alcoholism; May 2010
- "Epidemiology"; Alcohol Consumption and Urinary Concentration of 6-Sulfatoxtmelatonin in Healthy Women; R.G. Stevens et al.; November 2000
- "Alcohol and Alcoholism"; Alcohol Consumption Does Not Affect Melatonin Circadian Synchronization in Healthy Men; Thierry Danel and Yvan Touitou; July/August 2006
- "Neuropeptides"; Alcoholism Abolishes the Effects of Melatonin on Growth Hormone Secretion in Humans; V. Corio and P.P. Vescovi; June 1998
