From Plate to Pillow: How Food and Supplements Affect Your Sleep
A simple handful of cherries may improve your sleep.
Welcome to this edition of Sleepletter where we offer you easy-to-read insights from the latest research papers from the field of sleep neurobiology and clinical sleep medicine. We hope you enjoy the content!
Sleep and Food: A Delicious Interaction
The intricacies of sleep, a fundamental aspect of human physiology, are intertwined with various factors, including cultural practices and, notably, nutritional choices. Across the globe, we all eat different delicacies, but it’s the nutritional composition of them that can affect our sleep in meaningful ways. In this edition of Sleepletter, we delve into the scientific landscape that underscores the relationship between nutrition and the quality of our nightly repose.
Melatonin and the Chronobiology of Cherries
Within the realm of sleep physiology, melatonin assumes a pivotal role as a regulator intricately involved in circadian rhythms and the facilitation of transitions into restorative sleep phases. Broadening our comprehension, a spectrum of foods rich in melatonin becomes noteworthy contributors to this regulatory process. Cherries, notable for their inherent melatonin content, stand out as food high in melatonin content. For example, the juice from 100 grams of tart cherries, contains 0.135mg of melatonin. That’s pretty high considering that supplements people take start at roughly 1mg of melatonin. What’s more, dosages between 1 to 10 milligrams of supplemental melatonin can raise melatonin concentrations to anywhere from 3 to 60 times higher than typical physiological levels, thus making 200-400g of cherries already a pretty significant natural melatonin supplement which can help improve sleep quality and total sleep time. Extending beyond cherries - grapes walnuts, almonds, eggs, fish and olives serve as a pretty good source of melatonin from food too.
Tryptophan's Influence on Sleep
Tryptophan, an essential amino acid, plays a pivotal role in influencing sleep by serving as a precursor for the synthesis of important neurotransmitters, namely serotonin and melatonin. Serotonin, known for its mood-regulating properties, is actually a precursor for melatonin. The conversion of tryptophan to serotonin and subsequently to melatonin is a critical biochemical pathway that directly impacts sleep quality and the circadian rhythm. However, only a small portion (1–2%) of this dietary tryptophan is converted to melatonin via the serotonin pathway. Because of this, one has to be careful about easily interpreting that food rich in tryptophan influences sleep. Nonetheless, research has shown that foods rich in tryptophan (e.g. turkey, chicken, fish, dairy products, eggs, and tofu) can improve sleep quality.
Magnesium
Magnesium, a critical mineral abundantly found in a variety of dietary sources such as leafy greens, nuts, and seeds, wields a nuanced yet impactful influence on muscular relaxation, but it’s effects on sleep are not fully clear. Observational studies have found an association between magnesium and sleep quality, while more robust studies (e.g. randomized control trials) had contradictory findings.
Herbal Supplements
Chamomile and valerian root herbal supplements are often discussed for their potential to promote relaxation and support sleep, with scientific exploration rooted in neuropharmacology providing insights into their effects. These supplements contain bioactive compounds that interact with specific receptors in the brain, influencing neurotransmitter pathways associated with calming effects. Chamomile, for instance, contains apigenin, believed to have anxiolytic properties. Valerian root is thought to impact gamma-aminobutyric acid (GABA) receptors, contributing to relaxation. While anecdotal evidence and some studies suggest their sleep-inducing potential, it's essential to approach these claims cautiously, as individual responses can vary. Having said that, a review article concluded that valerian root seems to improve sleep quality without significant side effect, while another study showed the same results for chamomile.
From the melatonin-rich offerings of cherries to the neurotransmitter-influencing properties of tryptophan, each nutrient assumes a distinct role in modulating physiological processes. This nuanced understanding contributes to a comprehensive view of how nutritional science converges with the complexities of sleep physiology, offering insights into fostering a healthier and more restful night's sleep. While certain nutrients may be effective in promoting quality sleep, it's crucial to recognize that diet is just one of the factors influencing sleep. Eating specific foods cannot singularly replace other components of sleep hygiene, underscoring the importance of a holistic approach to optimizing sleep quality.
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About the author
Alen Juginović is a medical doctor and postdoctoral researcher in the Department of Neurobiology at Harvard Medical School studying the effect of poor sleep quality on health. He is keynote speaker and teacher at Harvard College. He and his team also organize international award-winning projects such as Nobel Laureate conferences, congresses with leaders in medicine, charity concerts and other events. Feel free to contact Alen via LinkedIn for any inquiries.