The Effects of Milk and Dairy Products on Sleep: A Systematic Review

Abstract

Several studies have assessed the effects of milk and dairy product intake on sleep quality and duration. Such investigations have varied in terms of their geographic locations, amounts of milk and dairy products, study participants (age, sex, race), and study designs. The present study aimed to summarize this literature and provide a unified view on whether the intake of milk and dairy products affects sleep quality. This systematic review was conducted according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The following keywords were chosen as electronic database search items from MeSH (medical subject headings) terms and descriptors in health sciences (DeHS) lists: milk, yogurt, dairy product, cheese, sleep, human, observational study, and interventional study. As a result, a total of 14 studies published between 1972 and 2019 were included in this review, including eight randomized controlled trials, two experimental studies with cross-over designs, one longitudinal study, and three cross-sectional studies. Four studies targeted older adults, three included toddlers, two targeted children, and six enrolled adults inclusive of university students. Overall, these studies indicated that a well-balanced diet that includes milk and dairy products is effective in improving sleep quality, despite mixed results across studies attributable to differences in study populations and methods.

The Relationship Between Dietary Intake and Sleep Quality in Endurance Athletes

“…Further, individuals that have less whole grain, vegetable, and fruit intake have more of an evening chronotype, i.e., they prefer to conduct activities in the evening which increases risk for sleep issues (Kanerva et al, 2012 ; Patterson et al, 2016 ). Moreover, milk and dairy foods has been linked to better sleep quality possibly because dairy foods contain the amino acid tryptophan a precursor for melatonin (Komada et al, 2020 ).…”

Association between adherence to the dietary approaches to stop hypertension (DASH) diet and maternal and infant sleep disorders

“…A well-balanced diet including milk and dairy products helps enhance sleep quality. The mechanism of action is thought to be that a high concentration of tryptophan, which is required to generate melatonin, found in milk and dairy products can inhibit the inhibitory neurotransmitter gamma-aminobutyric acid [ 35 ].…”

Nutritional Elements in Sleep

“…Additionally, turmeric has been shown to have a protective effect on neuronal loss due to chronic sleep deprivation through antioxidant properties in animal studies [ 86 ], but human studies are needed to establish such claims. The general consensus is that the intake of enriched milk and dairy products leads to anti-inflammatory and antioxidant changes in the brain-gut-microbiome axis and thus promotes good sleep [ 87 ]. Milk is a natural source of melatonin, and milk obtained through milking at night contains a higher content of melatonin and has a sleep-promoting effect [ 88 ].…”