当前，运用天然食物成份进行人类肿瘤的化学预防是国际上的重点研究课题。茶广泛的保健作用，自古以来就有记载。近年来，国内外科学家运用现代科学技术研究茶的防癌作用，取得了不少结果。迄今为止的研究表明：①能在体（人）内外阻断Ｎ－亚硝基化合物（致癌物）的合成；②能 At present, the use of natural food ingredients for chemoprevention of human tumors is a key research topic in the world. The extensive health benefits of tea have been documented since ancient times. In recent years, scientists at home and abroad have used modern science and technology to study the anti-cancer effects of tea and achieved many results. Studies so far have shown that: 1 It can block the synthesis of N-nitroso compounds (carcinogens) both inside and outside the body (human);