In the Yellow Emperor’s Classic of Internal Medicine, the Last Post of Su Wen – Treatise on the Method of Thrusting, there is a saying that “when righteousness exists in the body, evils cannot be interfered with”: only when the human body is strong and healthy will it be free from illnesses. The term “righteousness” refers to the ability to maintain the health of the human organism as well as the ability to adapt to the external environment, resist disease and recover. “Evil” refers to disease-causing factors. The occurrence of tumor can be summarized as follows: normal cells overgrow and proliferate abnormally which are not in accordance with the normal growth pattern under the long-term effect of internal factors such as heredity, endocrine or immune dysfunction, nutritional imbalance, mental and psychological stress, etc., and external factors such as physical, chemical and biological factors. The existence of positive qi enables the body to resist various factors inside and outside the body and prevent the occurrence of tumors. When positive qi exists within the body, the body is healthy. According to the health standards defined by the World Health Organization, one can simply judge whether one’s positive qi is sufficient or not: (1) Full of energy, able to cope with the pressures of daily life and work without excessive tension and fatigue. (2) Optimistic, positive attitude, willing to take responsibility, not picky about everything, and efficient at work. (3) Good at resting and sleeping well. (4) Resilient and able to adapt to various changes in the environment. (5) Resistant to disease, able to resist common colds and infectious diseases. (6) Proper weight, even stature, and coordinated position of head, shoulders, and arms when standing. (7) Bright, responsive eyes with non-inflamed eyelids. (8) Teeth are clean, free of cavities, caries, and pain; gums are normal in color and do not bleed. (9) Shiny hair, no dandruff. (10) Muscles and skin are elastic, walking easily and powerfully. So how to improve the positive qi? 1, nutrition: life diet and nutrition should be balanced, not only to eat a variety of grains and coarse grains, but also to eat a moderate amount of fresh fruits and vegetables, a sufficient amount of vegetables and fruits fiber, can prevent colorectal cancer, can reduce kidney cancer, breast cancer, esophageal cancer and other types of cancer incidence. 2.Exercise: Adhere to the safe and moderate amount of aerobic exercise, walk for 1 hour every day, can reduce half of the risk of colorectal cancer. Walking for 30 minutes after meals can reduce the risk of pancreatic cancer by half. 3.Water: Drink enough and clean water every day, and utilize hot and cold water to regulate the discomfort of the body. 4.Sunshine: Exercise outdoors more often and receive natural sunlight, of course, to prevent exposure to the sun. 5, moderation: moderation of desire and bad habits. Such as drinking alcohol in moderation, because alcohol inhibits the production of antibody B cells, increasing the chance of bacterial infection. A drunkenness is equivalent to a hepatitis. Adults should not consume more than 25 grams of alcohol a day, equivalent to 38 degrees of white wine should not exceed two. 6, air: more to the nature to breathe fresh air, as far as possible away from the second-hand smoke environment. In addition, smoking is not only related to lung cancer, but also makes people more prone to stomach cancer, colorectal cancer, cervical cancer, breast cancer and other cancers. 7.Rest: We should combine work and rest in our life, and maintain good resting habits and regular sleep. Frequent deduction of sleep time will sharply reduce the number of immune cells produced by the body. Staying up late for a long time will lead to immune dysfunction and trigger lymphoma. 8, mood: have a good mood, is the key to prevent cancer. If a woman loves to sulk, it can lead to endocrine disorders, resulting in high estrogen and insufficient luteinizing hormone, leading to the occurrence of breast diseases. Secondly, if a woman is under heavy pressure for a long time, her immune function will be greatly reduced, which will lead to unlimited proliferation of lymphatic tissues and increase the risk of cancer.