Table 6.
Variables selected for predicting dietary carbohydrate intake (%E) with their R2 and corresponding cross-validated R2 (%) using serum + 24-hour urine metabolites without participant characteristics or established diet-related biomarkers (Model 1).
| Variable# | Coefficient | R2 | CV-R2 |
|---|---|---|---|
| Intercept | −0.680 | ||
| Triacylglycerol (TAG 52:4(FA20:2)*) (serum) | 0.178 | 21.8% | 13.7% |
| Maltose (urine) | 0.042 | 8.8% | 5.5% |
| Phosphatidylcholine (PC 18:0/22:5*) (serum) | 0.142 | 8.6% | 5.4% |
| Triacylglycerol (TAG 54:1(FA20:0)*) (serum) | −0.103 | 4.8% | 3.0% |
| 3-hydroxypropionic acid (serum) | −0.104 | 3.7% | 2.3% |
| Glycochenodeoxycholate (serum) | 0.027 | 1.9% | 1.2% |
| Lysophosphatidylcholine (LPC 22:5*) (serum) | 0.050 | 2.9% | 1.8% |
| Phosphatidylethanolamine (PE 18:0/20:4*) (serum) | −0.083 | 1.8% | 1.1% |
| Ethylalcohol (urine) | −0.026 | 2.9% | 1.8% |
| Creatine (urine) | −0.022 | 1.1% | 0.7% |
| Phosphatidylcholine (PC 18:1/22:5*) (serum) | 0.042 | 0.6% | 0.4% |
| Triacylglycerol (TAG 50:4(FA14:1)*) (serum) | 0.040 | 0.1% | 0.1% |
| Cholesteryl ester (CE 20:2*) (serum) | 0.033 | 0.1% | 0.0% |
| Triacylglycerol (TAG 50:4(FA18:2)*) (serum) | −0.005 | 0.0% | 0.0% |
| Total | 59.0% | 37.1% |
Reordered by R2
The notation, TAG 52:4 (FA20:2) indicates that there are a total of 52 carbons with 4 double bonds in the three fatty acid chains of the lipid, of which one of the fatty acid (FA) chains contains 20 carbons with 2 double bonds.
PC 18:0/22:5 indicates that the lipid has two fatty acid chains, one has 18 carbons with 0 double bond and the other has 22 carbons with 5 double bonds.
TAG: triacylglycerol. PC:phosphatidylcholine. LPC: lysophosphatidylcholine. PE: phosphatidylethanolamine. CE: cholesterol ester.