Search

Objective: To assess whether monosodium glutamate (MSG) intake is associated with sleepdisordered breathing (SDB). Methods: Data from 1227 Chinese subjects who participated in the Jiangsu Nutrition Study were analyzed. All the participants were examined at two time points (baseline in 2002 and follow-up in 2007). The MSG intake was assessed quantitatively in 2002 and a sleep questionnaire was used to assess snoring and to construct an SDB probability score in 2007. Those within the fifth quintile of the score (highest) were defined as having a high probability of SDB. Results: The MSG intake was positively associated with snoring and a high probability of SDB in participants who had a normal body weight but in those who were overweight. A comparison of the extreme quartiles of MSG intake in subjects with a body mass index lower than 23 kg/m² showed an odds ratio of 2.02 (95% confidence interval 1.02-4.00) for snoring and an odds ratio of 3.11 (95% confidence interval 1.10-8.84) for a high probability of SDB. There was a joint effect between MSG and overweight in relation to SDB. Conclusion: The intake of MSG may increase the risk of SDB in Chinese adults with a normal body weight. [ABSTRACT FROM AUTHOR]

Background Soy isoflavone is beneficial for menopausal/postmenopausal symptoms, including sleep complaints. However, little is known about its longitudinal association with sleep in the general population. Objective Our aim was to investigate the association between soy isoflavone intake and sleep duration and daytime falling asleep among Chinese adults. Design A longitudinal analysis was performed. Soy isoflavone intake was assessed by food frequency questionnaire. Sleep duration was self-reported at two time points. Occurrence of daytime falling asleep was determined at follow-up. Short and long sleep were defined as sleep <7 h/day or ≥9 h/day, respectively. Participants/setting Adults aged 20 years and older from the Jiangsu Nutrition Study (2002-2007) with complete isoflavone intake and sleep duration data at both time points (n=1,474) were analyzed (follow-up, n=1,492). Main outcome measures We measured sleep duration in 2002 and 2007 and daytime falling asleep occurrence in 2007. Statistical analyses performed Mixed-effects logistic regression was performed for repeated measures between isoflavone intake and sleep duration. Logistic regression was performed for daytime falling asleep at follow-up. Demographic, anthropometric, and social factors were adjusted in the analyses. Results The prevalence of long sleep duration was 18.9% in 2002 and 12.6% in 2007, and the prevalence of daytime falling asleep was 5.3%. Compared with the lowest quartile of isoflavone intake, the highest quartile was associated with a lower risk of long sleep duration (odds ratio=0.66; 95% CI 0.48 to 0.90; P for trend=0.018) over 5 years. Compared with persistent low intake of isoflavone (less than median intake of isoflavone at two time points), persistent high intake was associated with a reduced risk of daytime falling asleep in women (odds ratio=0.20; 95% CI 0.06 to 0.68), but not men. No consistent association between soy isoflavone intake and short sleep duration was found. Conclusions Soy isoflavone intake was associated with a low risk of long sleep duration in both sexes and a low risk of daytime falling asleep in women but not men. [ABSTRACT FROM AUTHOR]