Regular consumption of sugar substitutes may trigger gastrointestinal discomfort, causing symptoms such as bloating, flatulence and diarrhea. The so-called sugar substitute, which is also a sweet substance that can replace refined sugar, brings sweetness but is not a carbohydrate, is not easily absorbed by the body and produces low calories. There are many types of sugar substitutes, including sorbitol, mannitol, xylitol and stevia. Sugar substitutes are not easily broken down by the digestive enzymes of the stomach, and eating too much of them can cause some gastrointestinal irritation, which may trigger a series of gastrointestinal symptoms, such as diarrhea, bloating and flatulence. In addition, sugar substitutes added to food can only reduce the energy intake brought about by the addition of traditional sweeteners, but cannot completely rely on sugar substitutes to control the diet. It is recommended that patients consume sugar substitutes reasonably under the guidance of a doctor, and seek prompt medical attention when discomfort occurs to avoid delays.