What is the mystery behind garlic's anti-cancer properties? It is well-known that nitrosamine compounds are one of the potent carcinogens identified, with dimethylnitrosoguanidine being the main culprit. Food microbiologists have pointed out that a microorganism named Clostridium botulinum is a nitrate-reducing bacterium in the stomach. It breaks down proteins in meat, converting them into organic amines, which are further transformed into dimethylnitrosamine, the culprit causing stomach cancer. Experimental studies have confirmed that the alkaloids in garlic, such as ethyl thiosulfinate and diallyl trisulfide, can inhibit the metabolism of Clostridium botulinum, thereby blocking the formation and accumulation of nitrites in the stomach. This deprives the culprit of stomach cancer of its breeding ground. Further scientific experiments have found that allicin in garlic can inhibit the sister chromatid exchange of lymphocytes caused by N-methyl-N-nitrosoguanidine and can directly kill stomach cancer cells. Garlic not only has unique functions in preventing and treating stomach cancer but also plays a special role in preventing other cancers. This is because garlic also contains a relatively large amount of selenium. Selenium is an antioxidant that can accelerate the decomposition of peroxides in the body, thereby depriving malignant tumors of their supply of molecular oxygen and thus exerting an anti-cancer effect. Selenium can also cause the human body to produce a large amount of glutathione. A high level of glutathione in the body is associated with a relatively lower incidence of cancer. According to research, glutathione has a unique function in fighting cancer. It uses its own chemical "handcuffs" to bind carcinogens, neutralizing their toxicity, and then expels them from the body through the digestive tract, thus defeating the cancer before it can take hold.