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Bioavailability of vitamin E in humans: an update
Patrick Borel1, Damien Preveraud, Charles Desmarchelier
1Institut National de la Santé et de la Recherche Médicale INSERM, Unité Mixte de Recherche UMR 1062, Nutrition, Obesity and Risk of Thrombosis, Marseilles, France. Patrick.Borel@univ-amu.fr
Nutrition Reviews
|June 5, 2013
Summary
Vitamin E absorption involves specific proteins like ABCA1, NPC1L1, and SR-BI. Its bioavailability varies significantly due to dietary factors, with many questions remaining about intestinal metabolism.
Area of Science:
- Nutritional Science
- Gastroenterology
- Biochemistry
Background:
- Vitamin E is crucial for human health, potentially preventing degenerative diseases.
- Its bioavailability is highly variable and influenced by multiple factors.
- Recent discoveries highlight the role of proteins in intestinal vitamin E absorption.
Purpose of the Study:
- To provide a current overview of vitamin E metabolization in the upper gastrointestinal tract.
- To evaluate factors affecting vitamin E bioavailability.
- To identify knowledge gaps in vitamin E intestinal absorption.
Main Methods:
- Review of existing literature on vitamin E metabolism and absorption.
- Systematic evaluation of dietary and molecular factors influencing bioavailability.
- Identification of key proteins involved in intestinal uptake.
Main Results:
- Proteins ATP-binding cassette transporter A1 (ABCA1), Niemann-Pick C1-Like 1 (NPC1L1), and Scavenger Receptor Class B Type 1 (SR-BI) are implicated in vitamin E absorption.
- Vitamin E absorption efficiency ranges widely (10-79%) and is influenced by the food matrix, fat content, and other fat-soluble micronutrients.
- Significant gaps exist in understanding intestinal lumen metabolization and absorption-influencing factors.
Conclusions:
- Specific proteins play a key role in the intestinal absorption of vitamin E.
- Dietary components significantly impact the variable efficiency of vitamin E absorption.
- Further research is needed to fully elucidate vitamin E intestinal metabolism and absorption dynamics.
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