Association Between Dietary Protein Intake and Sleep Quality in Middle-Aged and Older Adults in Singapore

Front Nutr. 2022 Mar 9:9:832341. doi: 10.3389/fnut.2022.832341. eCollection 2022.


Poor sleep has been associated with the increased risk of developing detrimental health conditions. Diet and certain nutrients, such as dietary protein (PRO) may improve sleep. This cross-sectional study aimed to investigate the relationship between PRO intake, their amino acid components, and sources with sleep quality in middle-aged and older adults residing in Singapore. A dataset of 104 healthy subjects between the age of 50 and 75 years old were used. Collected data included 3-day food record and sleep quality [sleep duration, global sleep score (GSS), sleep latency (SL), and sleep efficiency (SE)]. The collected 3-day food records were extracted for PRO, tryptophan (Trp), and large neutral amino acid (LNAA) intake. PRO intake was further categorized into plant and animal PRO. A multivariate multiple linear regression (MLR) was performed to assess the association between PRO intake and sleep quality. Dietary Trp:LNAA ratio was positively associated with sleep duration (βtotal: 108.234 h; p: 0.005) after multiple covariates adjustment. Similarly, plant Trp (βplant: 2.653 h/g; p: 0.020) and plant Trp:LNAA (βplant: 54.006 h; p: 0.008) was positively associated with sleep duration. No significant associations were observed for both SL and SE. Sleep duration in middle-aged and older Singaporean adults was positively associated with dietary Trp and Trp:LNAA, especially when obtained from plant sources.

Keywords: Trp:LNAA; animal protein; plant protein; plasma amino acid; sleep duration; sleep quality; tryptophan.