Increased permeability of the gastrointestinal mucosa is mostly seen in gastric and colon cancers due to necrosis and shedding of cancerous tissues, resulting in increased permeability of the corresponding gastrointestinal mucosa and loss of plasma proteins by leakage from the gastrointestinal tract. The treatment of increased permeability of gastrointestinal mucosa is mainly resection of the primary cancer tumor, but growth inhibitor analogues such as octreotide can also be applied, which is effective in controlling diarrhea. To overcome psychological barriers, patients will show characteristic reactions when they learn they have cancer. At first, the patient may be in doubt, denial or despair, and may say “this must be a mistake” and “what is the use of treatment”. Emotional irritability, anxiety, depression, physical insomnia, anorexia and irritability, lack of concentration and a sense of uncertainty about the future. Patients with increased permeability of the gastrointestinal mucosa should pay attention to a diet rich in dietary fiber; eat more easily digestible, fine and soft semi-fluid foods. Avoid cold, spicy and other stimulating foods; avoid greasy and fried foods; avoid pickled and smoked foods. The following foods are recommended to be avoided or not to be eaten: 1.Snail The snail is a cold food, which will aggravate the symptoms of colon cancer after consumption. In addition, rabbit meat, duck meat and eel are also better to be eaten sparingly. Crab is a high-protein food, which can aggravate the symptoms of colon cancer patients due to their poor physical condition. Mussels, clams, puffer fish and shrimps are also better to be eaten sparingly. 3.Salted vegetables Salted vegetables contain carcinogenic nitrite, which will aggravate the symptoms of colon cancer. Other pickled foods are also better to be eaten sparingly.