Table 5.
Variables selected for predicting dietary carbohydrate intake (g/d) with their R2 and corresponding cross-validated R2 (%) using serum + spot urine metabolites without participant characteristics or established diet-related biomarkers (Model 1).
| Variable# | Coefficient | R2 | CV-R2 |
|---|---|---|---|
| Intercept | 9.770 | ||
| Triacylglycerol (TAG 50:5(FA18:2)*) (serum) | 0.295 | 25.0% | 14.5% |
| Lysophosphatidylcholine (LPC 22:5*) (serum) | 0.102 | 8.6% | 5.0% |
| Triacylglycerol (TAG 50:4(FA18:1)*) (serum) | −0.332 | 7.6% | 4.4% |
| Cholesteryl ester (CE 22:2*) (serum) | 0.221 | 5.9% | 3.4% |
| Indole-3-propionate (serum) | 0.084 | 3.2% | 1.8% |
| Biliverdin (serum) | 0.030 | 2.2% | 1.3% |
| Triacylglycerol (TAG 50:3(FA14:0)*) (serum) | 0.197 | 1.8% | 1.1% |
| Triacylglycerol (TAG 48:4(FA14:1)*) (serum) | 0.121 | 1.7% | 1.0% |
| Creatine (serum) | −0.078 | 1.6% | 0.9% |
| Phosphatidylethanolamine (PE 18:0/20:4*) (serum) | −0.087 | 1.5% | 0.9% |
| Phosphatidylcholine (PC 18:0/20:2*) (serum) | 0.082 | 1.1% | 0.6% |
| Xanthurenic acid (serum) | −0.201 | 0.8% | 0.5% |
| Lysophosphatidylcholine (LPC 14:0*) (serum) | 0.056 | 0.7% | 0.4% |
| Phosphatidylcholine (PC 18:0/22:5*) (serum) | 0.095 | 0.4% | 0.3% |
| Triacylglycerol (TAG 52:4(FA20:2)*) (serum) | −0.006 | 0.0% | 0.0% |
| Total | 62.2% | 36.1% |
#
Reordered by R2
*
The notation, TAG 50:5 (FA18:2) indicates that there are a total of 50 carbons with 5 double bonds in the three fatty acid chains of the lipid, of which one of the fatty acid (FA) chains has 18 carbons with 2 double bonds. For LPE 16:0, 16 indicates number of carbons and 0 indicates number of double bonds in the fatty acid chain.
TAG: triacylglycerol. LPC: lysophosphatidylcholine. CE: cholesterol ester. PE: phosphatidylethanolamine. PC: phosphatidylcholine.