Table 2. Metabolite concentrations in urine of children aged 8–9 years old sampled daily over 6 days measured by 1H NMR spectroscopy.
| Metabolite concentration (μmol/mmol creatinine) | Daily Pool (n = 108) | Morning (n = 108) | Night (n = 108) |
|---|---|---|---|
| Creatinine (mmol/L) | 6.01 (4.6–7.29) | 6.12 (4.12–8.06) | 5.24 (3.94–7.21) |
| 2-hydroxyisobutyrate | 6.4 (5.8–7.6) | 6.8 (5.8–8.2) | 6.8 (5.7–7.7) |
| 3-hydroxyisobutyrate | 16.4 (12.5–21) | 15.1 (11.6–20) | 18.7 (13.2–23.8) |
| 4-deoxyerythronic acid | 12.5 (10–16.6) | 13.6 (10.8–19) | 13 (9.6–16.4) |
| 4-deoxythreonic acid | 21.3 (17.6–26.3) | 24.3 (18.8–27.8) | 18.7 (14.1–23.2) |
| Acetate | 9.1 (7.7–11.3) | 8.4 (6.5–10.1) | 11.4 (8.3–14.6) |
| Alanine | 58.9 (44.9–76.1) | 56 (42–67.9) | 65.7 (47–87.3) |
| Carnitine | 16.2 (8.9–24.7) | 14.6 (7.3–22.2) | 20.6 (11.2–31) |
| Citrate | 449.9 (332.4–567.1) | 370.3 (262.2–492) | 561.4 (352.6–698.8) |
| Creatine | 422.5 (260.8–616) | 358.5 (200.4–568.4) | 454.7 (306.4–663.6) |
| Dimethylamine | 63.4 (57–76.9) | 65 (57.8–74.7) | 62.9 (54.5–75.7) |
| Formate | 19.3 (13.8–26) | 17.4 (12–23.8) | 22.8 (14.7–30.4) |
| Glutamine | 133.3 (112–157.8) | 126.8 (102.1–145.4) | 135.6 (109.8–168.5) |
| Glycine | 117.1 (88.6–153.1) | 112.4 (75.3–155.9) | 125.5 (93–178.7) |
| Hippurate | 174 (111.1–249.9) | 173 (112.1–236.8) | 155.7 (92.5–242.8) |
| Isoleucine | 2 (1.6–2.3) | 1.9 (1.6–2.3) | 2.1 (1.6–2.6) |
| Lactate | 38.4 (31.4–47.9) | 36.3 (28.6–47.9) | 39.5 (30.6–57.8) |
| Leucine | 3.3 (2.8–3.7) | 3.2 (2.8–3.8) | 3.3 (2.6–4.2) |
| Lysine | 39.4 (26.7–55) | 41.1 (25–60.7) | 38.6 (25.8–53.8) |
| p-cresol sulfate | 47.1 (33.2–63.6) | 48.1 (30.8–68.2) | 47.4 (31.9–65) |
| Scyllo-inositol | 12.4 (8.4–15.2) | 10.7 (7.3–14.3) | 12 (8.1–17.2) |
| Succinate | 19.8 (13.4–27.8) | 18.6 (9.1–25.4) | 26.2 (15.5–35) |
| Taurine | 234.6 (195.3–329.1) | 209.6 (139.7–297.4) | 284.6 (222.4–364.5) |
| Trimethylamine | 4.4 (3.2–6.4) | 4.9 (3.4–6.4) | 4.8 (3.3–6.4) |
| Trimethylamine-N-oxide | 111.6 (80.5–216.5) | 94.3 (64.9–159.8) | 110.3 (80.9–210.7) |
| Valine | 6.5 (4.9–7.4) | 6.4 (5.1–7.6) | 6.7 (5.1–8.4) |
To correct for variations in urine concentration, values for all metabolites were normalised to creatinine. Median (interquartile range) are presented.