You should eat lots of them. Cutting down on fat allows you to increase your carbohydrate consumption. Carbohydrates also have more nutrients than sugars. Most Americans don't get enough dietary fiber. The two forms are soluble and insoluble.
Fiber helps to reduce the risk of heart disease and some forms of cancer.
You should consume 25-30 grams of fiber per day. Generally Americans eat too much protein, which means we are also getting too much cholesterol and fat. Some protein sources such as skim milk, beans and grains are better for you than others such as red meat and pork. The government established recommended daily allowances for vitamins and minerals. The best way to achieve this is through a balanced diet.