Certain foods naturally contain melatonin, a sleep-inducing hormone. The pineal gland in your brain normally produces melatonin and secretes the hormone into your blood at night. Melatonin regulates your circadian rhythm, a biological response to light and darkness and sleep and wakefulness over a 24 hour cycle. Supplements containing 3 mg or less of melatonin are popular remedies for insomnia. However, melatonin is an unapproved food additive, according to the FDA.
Tart cherries are a natural dietary source of melatonin. Scientists at the University of Texas Health Science Center in San Antonio found Montmorency and Balaton tart cherries contain high levels of melatonin compared to melatonin concentrations in the blood of mammals, according to research published in the "Journal of Agricultural and Food Chemistry" in October 2001. The scientists report Montmorency cherries contain significantly higher levels of melatonin than Balaton cherries -- approximately 13.46 ng per gram versus 2.06 ng per gram. The scientists also report the average human has between 5 to 10 pg of melatonin in the blood, which is equivalent to the quantity of melatonin in one Montmorency tart cherry. There have not been any clinical studies to date that demonstrate what effects eating tart cherries might have on human health with respect to melatonin content.
Walnuts are also a natural dietary source of melatonin. Walnuts contain 3.5 ng of melatonin per gram, according to research by scientists at the University of Texas Health Science Center in San Antonio and published in "Nutrition" in September 2005. The scientists found melatonin from walnuts absorbs into the blood and increases antioxidant activity. Melatonin is not only a strong sleep-inducing substance, but is also a powerful antioxidant that protects your cells from chemicals called free radicals that form inside your body and accelerate aging and stimulate the onset of cataracts and Alzheimer’s and Parkinson’s diseases. No clinical studies have been published that demonstrate an association between eating walnuts and neurodegenerative diseases or sleep disorders.
Scientists have tested few foods for melatonin content. Scientists at the University of Texas Health Science Center report sunflower seeds contain 29 ng of melatonin per gram, celery contains 7 ng of melatonin per gram and bananas contain 236 pg of melatonin per milligram, according to research published in "Nutrition Reviews" in September 2001. Melatonin concentrations vary widely in foods discovered to contain the hormone, and scientists do not yet know how a specific diet can influence sleep, jet lag or other circadian rhythm disorders.
Food manufacturers have begun to add melatonin to processed foods and beverages. However, melatonin is an unapproved food additive that can be dangerous. The FDA has warned food and beverage manufacturers that sell products which contain added melatonin that they violate the law and that these products may not be safe based on reports melatonin lowers blood pressure in humans and stimulates cancer and adversely effects the function of the retina in animals.
- Colorado State University: The Pineal Gland and Melatonin
- Food and Drug Administration: Warning Letter -- Melatonin
- Journal of Agricultural and Food Chemistry: Detection and Quantification of the Antioxidant Melatonin in Montmorency and Balaton Tart Cherries
- Nutrition: Melatonin in Walnuts -- Influence on Levels of Melatonin and Total Antioxidant Capacity of Blood
- University of Texas Health Science Center at San Antonio: Walnuts Contain Melatonin, Research Shows
- Nutrition Reviews: Melatonin in Plants
- Ablestock.com/AbleStock.com/Getty Images
This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.