British Journal of Nutrition

Research Article

Functional food science and gastrointestinal physiology and function

S. Salminena1, C. Bouleya2, M.-C. Boutrona3, J. H. Cummingsa4 c1, A. Francka5, G. R. Gibsona6, E. Isolauria7, M.-C. Moreaua8, M. Roberfroida9 and I. Rowlanda10

a1 Department of Biochemistry and Food Chemistry, University of Turku, SF-20500 Turku, Finland

a2 Groupe Danone, 15, Av. Galilée, F-92350 Le Plessis-Robinson, France

a3 U290 INSERM, Hôspital St Lazare, 107, rue du Faubourg Saint-Denis, F-75010 Paris, France

a4 Dunn Clinical Nutrition Centre, Hills Road, Cambridge CB2 2DH, UK

a5 Raffinerie Tirlernontoise - ORAFTI, Aandorenstraat I, B-3300 Tienen, Belgium

a6 Institute of Food Research, Reading Laboratory, Earley Gate, Reading RG6 6BZ, UK

a7 University of Tampere Medical School, PO Box 607, SF-33101 Tampere, Finland

a8 INRA - Unité d'Ecologie et de Physiologie du Systèrne Digestif, Bâitirnent 440 R-2, Domaine de Vilvert, F- 78352 Jouy-en-Josas Cedex, France

a9 UCL, Ecole de Pharmacie, Tour Van Helmont, Avenue E. Mounier, 73, B-1200 Brussels, Belgium

a10 University of Ulster, Coleraine BT52 ISA, UK

Abstract

The gut is an obvious target for the development of functional foods, acting as it does as the interface between diet and the metabolic events which sustain life. The key processes in digestive physiology which can be regulated by modifying diet are satiety, the rate and extent of macronutrient breakdown and absorption from the small bowel, sterol metabolism, the colonic microflora, fermentation, mucosal function and bowel habit, and the gut immune system. The intestinal microflora is the main focus of many current functional foods. Probiotics are foods which contain live bacteria which are beneficial to health whilst prebiotics, such as certain non-digestible oligosaccharides which selectively stimulate the growth of bifidobacteria in the colon, are already on the market. Their claimed benefits are to alleviate lactose maldigestion, increase resistance to invasion by pathogenic species of bacteria in the gut, stimulate the immune system and possibly protect against cancer. There are very few reports of well-designed human intervention studies with prebiotics as yet. Certain probiotic species have been shown to shorten the duration of rotavirus diarrhoea in children but much more work is needed on the mechanism of immunomodulation and of competitive exclusion and microflora modification. The develop-ment of functional foods for the gut is in its infancy and will be successful only if more fundamental research is done on digestive physiology, the gut microflora, immune system and mucosal function.

Correspondence:

c1 *Corresponding author: Dr J. H. Cummings, fax +44 (0)1223 413763, email john.cummings@mrc-dunn.cam.ac.uk