Kruger, JohanitaSus, NadineMoser, AndreaScholz, SophieAdler, GuentherVenturelli, SaschaFrank, Jan2024-10-222024-10-222024-09Kruger, J., Sus, N., Moser, A. et al. Low β-carotene bioaccessibility and bioavailability from high fat, dairy-based meal. European Journal of Nutrition 63, 2261–2270 (2024). https://doi.org/10.1007/s00394-024-03423-w.1436-6207 (print)1436-6215 (online)10.1007/s00394-024-03423-whttp://hdl.handle.net/2263/98704PURPOSE : The original aim of the study was to determine, in a double-blind 3-arm crossover human trial (n = 7), the effect of supplemental levels of iron (25 mg) and zinc (30 mg) on β-carotene (synthetic) bioavailability (10 h postprandial). However, despite the high dose of supplemental β-carotene (15 mg) consumed with the high fat (18 g), dairy-based breakfast test meal, there was a negligible postprandial response in plasma and triglyceride rich fraction β-carotene concentrations. We then systematically investigated the possible reasons for this low bioavailability of β-carotene. METHODS : We determined (1) if the supplemental β-carotene could be micellised and absorbed by epithelial cells, using a Caco-2 cell model, (2) if the fat from the test meal was sufficiently bioavailable to facilitate β-carotene bioavailability, (3) the extent to which the β-carotene could have been metabolised and converted to retinoic acid/retinol and (4) the effect of the test meal matrix on the β-carotene bioaccessibility (in vitro digestion) and Caco-2 cellular uptake. RESULTS : We found that (1) The supplemental β-carotene could be micellised and absorbed by epithelial cells, (2) the postprandial plasma triacylglycerol response was substantial (approximately 75–100 mg dL−1 over 10 h), indicating sufficient lipid bioavailability to ensure β-carotene absorption, (3) the high fat content of the meal (approximately 18 g) could have resulted in increased β-carotene metabolism, (4) β-carotene bioaccessibility from the dairy-based test meal was sixfold lower (p < 0.05) than when digested with olive oil. CONCLUSION : The low β-carotene bioavailability is probably due to a combination of the metabolism of β-carotene to retinol by BCMO1 and interactions of β-carotene with the food matrix, decreasing the bioaccessibility. TRAIL REGISTRATION : The human trail was retrospectively registered (ClinicalTrail.gov ID: NCT05840848).en© The Author(s) 2024. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License.BioaccessibilityCellular uptakeDivalent mineralsFood matrixLipid profileMicellizationDairyBCMO1SDG-02: Zero hungerArticle