Associations of Tryptophan, Docosahexaenoic Acid (DHA), and Vitamin D With Sleep Quality and Depression During Pregnancy

Abstract

Objectives During pregnancy women are at increased risk of poor sleep quality and depression. Serotonin and melatonin are compounds that are involved in regulation of sleep and mood. Several nutrients are involved in the synthesis of these compounds, including tryptophan, docosahexaenoic acid (DHA), and vitamin D. Studies exploring associations between these nutrients and sleep, as well as mood, have been largely limited to the general population, showing mixed results. The aim of this study was to assess the associations of dietary intake of these nutrients with sleep quality and depression in pregnant women. Methods Participants enrolled in the Understanding Pregnancy Signals and Infant Development (UPSIDE) Study (n = 253) were included in this analysis if they completed dietary, sleep and depression assessments during the 2nd trimester. Dietary and supplement intake were measured using 24-hour dietary recalls. The NCI method was used to estimate usual intake. Sleep quality was measured with the Pittsburgh Sleep Quality Index (PSQI). Depressive symptoms were measured with the Edinburgh Postnatal Depression Scale (EPDS). Multivariable linear regression was conducted to estimate the associations between nutrients and sleep/depression, adjusting for age, race/ethnicity, parity, education, early pregnancy body mass index, smoking status, energy and macronutrient intake. Results The NCI adjusted mean intakes of tryptophan, DHA, and vitamin D were 1.02 ± 0.11 g/day, 0.13 ± 0.11g/day, and 19.74 ± 21.80 mcg/day, respectively. Mean PSQI score was 6.15 ± 3.39, where higher scores indicated worse sleep quality, and mean EPDS score was 5.84 ± 4.77, where higher scores indicated increased severity of depressive symptoms. Tryptophan intake was inversely associated with EPDS scores (b = –15.23, 95%CI: –26.75, –3.72). The associations between DHA, vitamin D, and depression were not significant. The selected nutrients were not associated with PSQI scores. Conclusions In this study, higher tryptophan intake was associated with lower depressive symptoms among pregnant women during the second trimester. Additional research on the relationship between tryptophan intake and maternal mental health during pregnancy is warranted. Funding Sources NIH, Mae Stone Goode Foundation, Wynne Family Foundation.