Table 3.

Percentage difference in geometric mean metabolite LC-MS peak areas, by fasting timea

Fasting 9–12 vs. ≥13 hFasting 5–8 vs. ≥13 hFasting ≤4 vs. ≥13 h
Metabolite categoryNFasting ≥13 hPercentage difference, median (10th–90th percentiles)Percentage of metabolites within 15% of referentPercentage difference, median (10th–90th percentiles)Percentage of metabolites within 15% of referentPercentage difference, median (10th–90th percentiles)Percentage of metabolites within 15% of referent
Amines5Referent−2.7 (−10.6 to 2.4)100%−4.6 (−21.0 to 6.5)80%−2.9 (−16.3 to 6.7)80%
Amino acid derivatives13Referent1.5 (−5.5 to 8.2)100%−2.7 (−11.4 to 3.7)92%4.8 (−3.8 to 24.6)77%
Amino acids28Referent2.0 (−3.8 to 5.3)96%−2.4 (−9.4 to 10.8)96%2.8 (−5.5 to 20.7)86%
Bile acids5Referent0.4 (−8.4 to 17.4)80%−11.3 (−29.1 to 18.7)60%53.1 (3.0 to 129.9)20%
Lipids and lipid metabolites88Referent0.2 (−4.6 to 8.6)98%0.5 (−3.8 to 10.7)92%0.9 (−4.5 to 26.4)83%
Organic acids11Referent−5.1 (−13.7 to 3.5)91%0.6 (−4.3 to 10.2)91%−0.6 (−18.1 to 10.7)73%
Purines, pyrimidines, and derivatives3Referent−1.2 (−2.9 to 1.8)100%−3.9 (−7.4 to −1.7)100%−2.6 (−26.6 to 0.7)67%
Vitamins3Referent7.6 (0.8 to 10.4)100%9.6 (9.2 to 16.0)67%58.6 (24.1 to 77.3)0%
Otherb10Referent−0.4 (−16.4 to 10.7)90%−2.8 (−24.0 to 18.6)50%12.4 (−24.2 to 84.5)30%
  • NOTE: N, number of metabolites.

  • aGeometric means were adjusted for age at blood draw (years, continuous), race (white, non-white), body mass index (continuous, kg/m2), physical activity (metabolic equivalent-hr/wk, continuous), sex/menopausal status (female/premenopausal, female/postmenopausal and no hormone therapy use, female/postmenopausal and hormone therapy use, male), and total caloric intake (kcal, continuous).

  • bOther metabolites include allantoin, cotinine, creatine, creatinine, hippurate, hydroxyphenylacetate, phenylethylamine, salicylurate, sorbitol, and uracil.