Gut: The Inside Story of Our Body’s Most Underrated Organ

by Giulia Enders

1. There is a certain foodstuff we can eat to nudge the gut wall into action: fiber. Dietary fiber is not digested in the small intestine and can knock on the wall of the large intestine in a friendly way to say there is someone here who wants to be shown the way out. The best results are produced by psyllium seed husks and the rather more pleasant-tasting plum. Both contain not only fiber, but also agents that draw extra fluids into the gut—making the whole business smoother. It can take two to three days before their effect is felt. So, you can start eating them either a day before your trip or on the first day—whatever feels safer. Those with no plum compartment in their suitcase can buy dietary fiber in tablet or powdered form from their pharmacy or drug store. One ounce (30 grams) is an appropriate daily dose of dietary fiber. There are two kinds of fiber: water-soluble and insoluble. The latter is better at stimulating movement through the digestive system, but it can often cause stomachaches. Water-soluble fiber does not provide quite such a powerful push, but it does make the contents of the gut softer and easier to deal with. Nature’s design is rather clever: the skins of many fruits contain large amounts of insoluble fiber, while the flesh of the fruit contains more soluble fiber.