Imperial College London


Faculty of MedicineDepartment of Medicine

Chair in Nutrition and Dietetics



+44 (0)20 3313 8037g.frost Website




Commonwealth BiuldingHammersmith HospitalHammersmith Campus






BibTex format

author = {Gibbons, H and Michielsen, CJR and Rundle, M and Frost, G and McNulty, BA and Nugent, AP and Walton, J and Flynn, A and Gibney, MJ and Brennan, L},
doi = {10.1002/mnfr.201700037},
journal = {Mol Nutr Food Res},
title = {Demonstration of the utility of biomarkers for dietary intake assessment; proline betaine as an example.},
url = {},
volume = {61},
year = {2017}

RIS format (EndNote, RefMan)

AB - SCOPE: There is a dearth of studies demonstrating the use of dietary biomarkers for determination of food intake. The objective of this study was to develop calibration curves for use in quantifying citrus intakes in an independent cohort. METHODS AND RESULTS: Participants (n = 50) from the NutriTech food-intake study consumed standardized breakfasts for three consecutive days over three consecutive weeks. Orange juice intake decreased over the weeks. Urine samples were analyzed by NMR-spectroscopy and proline betaine was quantified and normalized to osmolality. Calibration curves were developed and used to predict citrus intake in an independent cohort; the Irish National Adult Nutrition Survey (NANS) (n = 565). Proline betaine displayed a dose-response relationship to orange juice intake in 24 h and fasting samples (p < 0.001). In a test set, predicted orange juice intakes displayed excellent agreement with true intake. There were significant associations between predicted intake measured in 24 h and fasting samples and true intake (r = 0.710-0.919). Citrus intakes predicted for the NANS cohort demonstrated good agreement with self-reported intake and this agreement improved following normalization to osmolality. CONCLUSION: The developed calibration curves successfully predicted citrus intakes in an independent cohort. Expansion of this approach to other foods will be important for the development of objective intake measurements.
AU - Gibbons,H
AU - Michielsen,CJR
AU - Rundle,M
AU - Frost,G
AU - McNulty,BA
AU - Nugent,AP
AU - Walton,J
AU - Flynn,A
AU - Gibney,MJ
AU - Brennan,L
DO - 10.1002/mnfr.201700037
PY - 2017///
TI - Demonstration of the utility of biomarkers for dietary intake assessment; proline betaine as an example.
T2 - Mol Nutr Food Res
UR -
UR -
VL - 61
ER -