In a recent study published in the Nutrients Journal, researchers conducted a systematic literature review to understand the association between the dietary intake of pregnant individuals and sleep duration and quality.

Study: A Systematic Review of Studies Examining Associations between Sleep Characteristics with Dietary Intake and Eating Behaviors during Pregnancy. Image Credit: Dean Drobot/Shutterstock.com

Background

The two major factors during pregnancy that undergo substantial changes but also play a significant role in the health of the mother and the fetus are diet and sleep. During gestation, both sleep quality and duration are significantly reduced.

Lower quality and shorter duration of sleep among pregnant women have been linked to adverse outcomes such as preterm birth, an increased risk of gestational diabetes, longer labor, higher gestational weight gain, and a higher probability of Cesarean delivery.

The dietary requirements of pregnant women also undergo significant changes, especially during the last two trimesters, to support the growth and development of the fetus.

While various published guidelines recommend an increased intake of proteins and calories, a reduction in the consumption of saturated fats and beverages sweetened with sugar, and supplementation with folate, omega-3 fatty acids, iron, choline, Vitamin D, iodine, and calcium are also recommended.

The association between diet and sleep has been extensively studied in the general population, with findings indicating that carbohydrates and dairy products decrease the onset latency and increase the duration of sleep, respectively, while caffeine reduces the quality and duration of sleep and increases the onset latency.

However, the association between dietary changes during pregnancy and sleep quality has not been systematically explored.

About the study

In the present study, the researchers included peer-reviewed articles that were published in English, presented quantitative outcomes from original research, and included at least one maternal pregnancy-related measure, and one variable, each related to diet and sleep.

The eligible articles could have additional variables related to infant health or the postpartum period, but the association between a minimum of one diet-related variable and a sleep-related variable was mandatory.

Results

The results reported that although some of the included studies reported significant findings, the studies that examined the association between diet and maternal sleep were largely heterogeneous, making it difficult to conduct a meta-analysis or arrive at conclusions about the association.

The studies varied across a wide range of parameters, including the examined outcomes and exposures, definitions of these outcomes and exposures, sample size, study period, ethnic and racial representation in the study population, weight status of pregnant individuals in the study population, methodology of evaluating sleep, as well as the dietary variables.

While some studies had a large sample size of over 10,000 participants, others included around 100 individuals. The period of study varied from a specific trimester to any time across the duration of the pregnancy.

Some studies examined pregnant individuals of varied weight statuses, while others focused on individuals who were overweight or obese before the pregnancy. The dietary variables across different studies were also significantly different, with some studies examining dietary patterns, specific food groups, and nutrient intake and others considering only dietary intake and quality.

Furthermore, although most studies used a subjective questionnaire to assess sleep quality, the methodologies differed widely.

Most of the studies that examined the association between sleep quality and energy intake found that calorific intake had no impact on sleep duration or quality. One study found that the energy intake of obese women decreased during pregnancy as they increased the time spent in bed.

While another study found that although the sleep duration remained average, women who experienced adverse sleep symptoms had a higher calorific intake than women who did not experience any adverse symptoms related to sleep.

Although the two studies that examined the association between fat intake and sleep were not consistent in their assessments of diet fat or sleep quality. The overall findings indicated that the intake of dietary fat was linked to disturbed sleep, and pregnant women who consumed lower amounts of monounsaturated fats experienced adverse sleep symptoms.

Similar patterns were also observed in studies that examined the association between carbohydrate intake and sleep quality, although the results were not significant enough to draw strong conclusions.

Conclusions

Overall, the findings indicated that while some association was observed between dietary intake of fats and carbohydrates and sleep duration and quality, the heterogeneity across the studies examining these associations made it difficult for the researchers to conduct a meta-analysis or draw strong conclusions.

The review highlights the need for consistency in the measured outcomes, exposures, and methodology across studies that examine associations between maternal diet and sleep quality during pregnancy.

Written by

Dr. Chinta Sidharthan

Chinta Sidharthan is a writer based in Bangalore, India. Her academic background is in evolutionary biology and genetics, and she has extensive experience in scientific research, teaching, science writing, and herpetology. Chinta holds a Ph.D. in evolutionary biology from the Indian Institute of Science and is passionate about science education, writing, animals, wildlife, and conservation. For her doctoral research, she explored the origins and diversification of blindsnakes in India, as a part of which she did extensive fieldwork in the jungles of southern India. She has received the Canadian Governor General’s bronze medal and Bangalore University gold medal for academic excellence and published her research in high-impact journals.