许多医生推荐含有丰富食物纤维的天然食物，因为它有助于防止便秘，以取代万不得已而使用的泻药。原因显而易见－治病总是不如防病。

Many doctors prefer a natural food, rich in dietary fibre, which will help you to avoid constipation, rather than having to resort to purgatives. The reason is obvious-prevention is always better than cure.