Table 4.
Validation scheme of potential food intake biomarkers for vegetable oils
| Dietary factor [references] | Compound/metabolite | HMDB ID | Sample type | Criteria | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3a | 3b | 4 | 5 | 6 | 7 | 8 | ||||
| Olive oil [128, 133, 134, 141, 142, 157, 158] | Oleic acid | HMDB0000207 | Plasma/blood cells | N | U | Y | Y | Y | U | U | Y | U |
| Olive oil, (extra) virgin [80, 135, 136, 144–150, 143, 151] | Hydroxytyrosol | HMDB0005784 | Urine/plasma | Y | Y | Y | U | Y | U | U | Y | U |
| Olive oil, (extra) virgin [137, 138, 153–155, 152, 156] | Hydroxytyrosol sulfate | – | Urine/plasma | Y | Y | Y | U | Y | Y | U | Y | U |
| Olive oil, (extra) virgin [139, 140, 155, 156] | Hydroxytyrosol acetate sulfate | – | Urine/plasma | Y | U | Y | U | Y | U | U | Y | U |
| Olive oil, (extra) virgin [136, 150, 151] | 3-O-Methylhydroxytyrosol | – | Urine | Y | Y | U | U | Y | U | U | Y | U |
| Flaxseed/linseed oil [160–165] | α-Linolenic acid | HMDB0001388 | Plasma/serum/erythrocytes/platelets | N | Y | U | Y | Y | U | U | Y | U |
| Rapeseed/canola oil [158, 175–178, 174, 179] | α-Linolenic acid | HMDB0001388 | Plasma/platelets/breast milk | N | Y | Y | U | Y | U | U | Y | U |
| Sunflower oil [157, 173, 179, 178, 180] | Linoleic acid | HMDB0000673 | Plasma/platelets/subcutaneous adipose tissue | N | U | U | U | Y | U | U | Y | U |
HMDB human metabolome database, N no, U unknown, Y yes. Criteria: C1—Plausibility, Is the marker compound plausible as a specific BFI for the food or food group?; C2—Dose response, Is there a dose-response relationship at relevant intake levels of the targeted food?; C3—Time response, Is the biomarker kinetics described adequately to make a wise choice of sample type, frequency and time window?; C3a, single dose; C3b, multiple doses; C4, Robustness, Has the marker been shown to be robust after intake of complex meals reflecting the dietary habits of the targeted population?; C5, Reliability, Has the marker been shown to compare well with other markers or questionnaire data for the same food/food group?; C6, Stability, Is the marker chemically and biologically stable during biospecimen collection and storage, making measurements reliable and feasible?; C7, Analytical performance, Are analytical variability (CV%), accuracy, sensitivity and specificity known as adequate for at least one reported analytical method?; C8, Reproducibility, Has the analysis been successfully reproduced in another laboratory?