TABLE 1.
Substrate and hormone concentrations, kinetic measures, energy expenditure (EE), and substrate oxidation after the overnight fast1
| All women (n = 14) |
Nonlactating women (n = 7) |
Lactating women (n = 7) |
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| Glucose | Galactose | Glucose | Galactose | Glucose | Galactose | |
| Glucose (mmol/L) | 5.10 ± 0.08 | 5.09 ± 0.8 | 5.23 ± 0.12 | 5.10 ± 0.07 | 4.97 ± 0.09 | 5.09 ± 0.15 |
| Insulin (μU/mL) | 12.3 ± 2.2 | 9.5 ± 1.2 | 17.5 ± 4.3 | 13.0 ± 2.2 | 7.0 ± 1.1 | 6.0 ± 0.9 |
| C-peptide (ng/mL) | 3.0 ± 0.4 | 2.4 ± 0.3** | 3.5 ± 0.7 | 2.8 ± 0.5 | 2.5 ± 0.3 | 2.0 ± 0.2* |
| Galactose (μmol/L) | 21 ± 2 | 20 ± 2 | 14 ± 3 | 13 ± 3 | 28 ± 3 | 27 ± 3 |
| Lactate (mmol/L) | 0.95 ± 0.1 | 0.86 ± 0.1 | 1.06 ± 0.1 | 1.04 ± 0.09 | 0.83 ± 0.1 | 0.67 ± 0.0 |
| β-Hydroxybutyrate (mmol/L) | 115 ± 13 | 116 ± 11 | 67 ± 15 | 49 ± 14 | 163 ± 22 | 184 ± 16 |
| FFA (μmol/L) | 637 ± 52 | 610 ± 43 | 529 ± 47 | 504 ± 57 | 745 ± 92 | 717 ± 67 |
| Cholesterol (mg/dL) | 169 ± 10 | 161 ± 8** | 174 ± 16 | 165 ± 13* | 164 ± 11 | 158 ± 10 |
| LDL (mg/dL) | 103 ± 8 | 96 ± 6* | 109 ± 13 | 100 ± 11* | 97 ± 9 | 93 ± 7 |
| HDL (mg/dL) | 44 ± 3 | 40 ± 3** | 39 ± 3 | 33 ± 2* | 49 ± 4 | 46 ± 4 |
| Triglycerides (mg/dL) | 106 ± 14 | 132 ± 13** | 124 ± 15 | 167 ± 15** | 87 ± 18 | 96 ± 23 |
| Glycerol (μmol/L) | 76 ± 5 | 71 ± 5 | 59 ± 5 | 55 ± 3 | 92 ± 8 | 87 ± 9 |
| Palmitate (μmol/L) | 152 ± 10 | 138 ± 7 | 120 ± 11 | 108 ± 7 | 184 ± 17 | 168 ± 18 |
| Palmitate/FFA | 0.24 ± 0.01 | 0.23 ± 0.01 | 0.23 ± 0.02 | 0.23 ± 0.02 | 0.26 ± 0.02 | 0.24 ± 0.02 |
| HOMA | 2.86 ± 0.70 | 2.15 ± 0.36 | 4.21 ± 1.21 | 2.95 ± 0.56 | 1.52 ± 0.24 | 1.35 ± 0.20 |
| QUICKI | 0.34 ± 0.01 | 0.35 ± 0.01 | 0.35 ± 0.01 | 0.35 ± 0.01 | 0.36 ± 0.01 | 0.37 ± 0.01 |
| Glucose Ra (μmol−1 · kg−1 · min−1)2 | 8.15 ± 0.22 | 7.91 ± 0.23 | 7.10 ± 0.31 | 7.09 ± 0.31 | 9.19 ± 0.30 | 8.73 ± 0.33* |
| Glycerol Ra (μmol−1 · kg−1 · min−1)2 | 2.55 ± 0.13 | 2.46 ± 0.15 | 2.13 ± 0.18 | 2.07 ± 0.17 | 2.98 ± 0.19 | 2.84 ± 0.25 |
| Palmitate Ra (μmol−1 · kg−1 · min−1)2 | 1.47 ± 0.10 | 1.38 ± 0.10 | 1.26 ± 0.10 | 1.22 ± 0.11 | 1.68 ± 0.16 | 1.55 ± 0.17 |
| FFA Ra (μmol−1 · kg−1 · min−1)2 | 6.21 ± 0.54 | 6.06 ± 0.49 | 5.67 ± 0.61 | 5.56 ± 0.54 | 6.57 ± 0.89 | 6.56 ± 0.81 |
| RQ | 0.82 ± 0.01 | 0.82 ± 0.01 | 0.83 ± 0.01 | 84 ± 0.01 | 0.81 ± 0.01 | 0.80 ± 0.01 |
| EE (kcal/d) | 1501 ± 26 | 1479 ± 31 | 1485 ± 41 | 1475 ± 56 | 1518 ± 32 | 1483 ± 29 |
| Fat oxidation (g/d) | 84 ± 4 | 80 ± 6 | 82 ± 6 | 72 ± 9 | 86 ± 5 | 88 ± 6 |
| CHO oxidation (g/d) | 147 ± 11 | 144 ± 10 | 155 ± 17 | 169 ± 17 | 140 ± 15 | 119 ± 12 |
| Protein oxidation (g/d) | 37 ± 5 | 42 ± 7 | 32 ± 5 | 37 ± 4 | 42 ± 9 | 46 ± 12 |
1
All values are means ± SEMs. RQ, respiratory quotient; FFA, free fatty acid; Ra, rate of appearance; CHO, carbohydrate; HOMA, homeostasis model of assessment; QUICKI, quantitative insulin-sensitivity check index. Post hoc procedures provided by Generalized Estimating Equations were used to perform the comparisons of glucose and galactose within groups and in all women combined. *,**Significant difference between the glucose and galactose diets: *P < 0.05, **P < 0.01.
2
Based on total body weight.