The ISBN 9781454937661 corresponds to the book Melatonin: The Natural Supplement for Better Sleep by Locke Hughes, published by Sterling Ethos in 2019. This informative guide delves into the role of melatonin, a hormone that regulates sleep and the body's circadian rhythm. It explores how melatonin affects the body, offers guidance on safe supplementation, and includes 20 recipes featuring foods that promote natural melatonin production. Additionally, the book provides 30 ideas for calming bedtime rituals and routines to help readers achieve restful sleep.