Dietary fiber is a kind of indigestible food nutrient. It mainly comes from plant cell walls and contains cellulose, hemicellulose, resin, pectin and lignin. Dietary fiber is indispensable for a healthy diet. Fiber plays an important role in keeping the digestive system healthy. At the same time, taking enough fiber can also prevent cardiovascular diseases, cancer, diabetes and other diseases. Fiber can clean the digestive wall and enhance the digestive function. At the same time, fiber can dilute and accelerate the removal of carcinogens and toxic substances in food, protect the fragile digestive tract and prevent colon cancer. Fiber can slow down digestion and excrete cholesterol as quickly as possible, so it can control blood sugar and cholesterol at the best level. Brown rice and embryo polished rice, as well as miscellaneous grains such as corn, millet, barley, wheat bran and wheat flour (the material of black bread); In addition, there are many dietary fibers in root vegetables and seaweed, such as burdock, carrot, mung bean, red bean, pea, potato and Undaria pinnatifida. Dietary fiber is a plant component, and plant food is a natural food source of dietary fiber. Vegetables, fruits, coarse grains, beans and bacteria and algae are rich in dietary fiber.