Mechanistic Effect of Walnut Consumption on Sleep Quality
Columbia University
Summary
Poor sleep quality is very common in modern society. Walnuts contain many nutrients that may be helpful for sleep, including melatonin and polyphenols. Some studies show that eating foods high in melatonin and polyphenols improves sleep quality, but walnuts have not been studied specifically. This study proposes to test if eating walnuts improves sleep compared to a food that lacks these sleep-promoting factors. The investigators expect that walnut consumption for 4 days will increase melatonin levels and lead to better sleep quality compared to a high-carbohydrate, high-sugar food. The study will enroll middle-aged and older adults with sleep complaints to participate in this study. Each person will eat the two different foods for 4 days each in random order. The 4-day periods will be separated by at least 2-3 weeks. Sleep quality will be measured by questionnaire and with a wrist monitor every day. The investigators will also do a sleep study using electroencephalography (EEG) on night 3 and take measures of circadian physiology (natural body rhythms) in the laboratory on day 4 (including overnight) by measuring body temperature and blood and urine melatonin. The study findings may provide new options to improve sleep health from increased walnut consumption.
Description
Walnuts are a nutrient-rich food which provides melatonin and polyphenols. While there is evidence that dietary intakes of foods high in melatonin and polyphenols positively influence sleep quality, the effect of walnuts has not been investigated. The investigators propose to fill this knowledge gap by testing the effects of walnut consumption on serum melatonin and resulting sleep and circadian biology. The study hypotheses are that walnut consumption for 4 days will increase melatonin levels, suggestive of more robust circadian rhythms, and lead to better sleep quality compared to a high-car…