Dietary Intake of Nε-carboxymethyl-lysine, a Major Advanced Glycation End Product, is Not Associated with Increased Risk of Mortality in Japanese Adults in the Takayama Study.

Background: Although endogenous advanced glycation end products (AGEs) have been implicated in the development of various chronic diseases, whether AGEs in foods represent a risk to human health remains unknown.

Objectives: We aimed to estimate the intake of Nε-carboxymethyl-lysine (CML), a major AGE product, using a database of CML contents on LC-MS methods, and to examine CML's association with total and cause-specific mortality in Japanese adults.

Methods: The analysis included 13,355 men and 15,724 women, aged 35 years and older, from the Takayama study. They responded to a self-administered questionnaire in 1992. Their diet, including the CML intake, was assessed using a food-frequency questionnaire at baseline. Mortality was ascertained during 16 years of follow-up. HRs and 95% CIs for mortality were estimated separately for men and women according to CMI quartiles.

Results: We noted 2901 deaths in men and 2438 deaths in women during the follow-up. In men, as compared with the lowest quartile of intake, the highest quartile of CML was inversely associated with the risks of both total and non-cancer, non-cardiovascular disease mortality after controlling for covariates [HR = 0.89 (95% CI, 0.79-1.00; P-trend = 0.047) and HR = 0.74 (95% CI, 0.58-0.94; P-trend = 0.03), respectively]. However, stratified analyses showed both inverse and positive associations between CML intake and cause-specific mortality in women, depending on their characteristics. For example, years of education had a modifying effect on both the CML intake and non-cancer, non-cardiovascular disease mortality in women. In men, the associations of CML intake with mortality depended on food sources.

Conclusions: Overall, the present study does not support a positive association between CML intake and mortality in Japanese adults. The potential relevance of the food source of CML to the link between dietary CML and mortality warrants further attention.