Abstract
It is now clear that both chemical composition and physical properties of the intestinal microvillus membrane are critically important in determining its transport function. Recent advances in this field have been made in research laboratories around the world, and it is important that such data be put in a clinical perspective. The concept of membrane fluidity and the ability to regulate this membrane parameter either pharmacologically or by diet is now an important concept in systemic and local gastrointestinal disease. This review gives an overview of membrane physical properties, how they are measured, and their relationship to nutrient absorption in the intestinal tract. It is not intended to be all inclusive and expressly attempts to make these concepts simple.