Figure 1
![Figure 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2F1741-7015-9-24/MediaObjects/12916_2011_Article_373_Fig1_HTML.jpg)
The intestine's impact on health. The gastrointestinal tract contributes to health by ensuring digestion and absorption of nutrients, minerals and fluids; by induction of mucosal and systemic tolerance; by defence of the host against infectious and other pathogens; and by signalling from the periphery to the brain. For details and references, see text 'Underlying mechanisms'.