Objective   To explore the relationship between different carbohydrate/fat intake ratio and aging biomarkers under normal energy and protein intake in healthy people.

  Methods  Form 4 973 adult residents participating in Harbin Cohort Study on Diet, Nutrition and Non-Communicable Chronic Diseases conducted in 2015, we selected 90 healthy people reporting normal dietary protein and energy intake but without personal and family history of chronic disease and divided them into three groups (30 in each group): normal control (N), high fat (HF) and high carbonhydrate (HC) group. Ultrahigh performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-Tof-MS) was used to detect metabolic fingerprints of plasma samples of the participants. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were employed to analyze differences in metabolites among the participants of different age group. Aging biomarkers were screened out according to the values of variable importance in the projection (VIP) and variation ratio obtained by PLS-DA model, and changes in the aging biomarkers in different dietary groups were analyzed.

  Results  The results of UPLC-Q-Tof-MS showed that all the study groups could be distinguished accurately under PLS-DA mode and there were significant differences in plasma metabolic mode. Five aging biomarkers were identified; among which, 12 (s)-hpete, aminoadipic acid and 3-hydroxynonylcarnitine increased with age, while L-leucine and dehydroe-piandrosterone sulfate decreased with age. In comparison with those of the N group, the concentrations of L-leucine and dehydroepiandrosterone sulfate of the HF and the HC group decreased, but the concentrations of 12 (s)-hpete, aminoadipic acid and 3-hydroxynonylcarnitine of the two groups increased. Compared with the HF group, the HC group had decreased L-leucine and dehydroepiandrosterone sulfate but increased 12 (s)-hpete, aminoadipic acid and 3-hydroxynonanoylcarnitine. The results suggested that both high-fat and high carbohydrate could promote aging to some extent, and the effect of high carbohydrate on aging is more obvious.

  Conclusion  Under the same energy and protein intake, high-fat and high carbohydrate intake are not conducive to healthy life span; compared with high-fat intake, high carbohydrate intake is easier to promote aging process and shorten life expectancy.