It is not true that sunlight can cure cancer. First of all, the ultraviolet rays of the sun only have the effect of sterilization, which can kill and remove some bacteria; secondly, the sunlight can only contact with the human skin, and can only act on the surface of the skin, while the cancer cells cannot be in the surface layer of the skin, but are distributed in the deeper parts of the human body, which can’t be contacted with the sunlight at all, therefore, there is no role of sunbathing in the treatment of cancer. On the contrary, prolonged exposure to the sun will lead to hyperpigmentation, darkening and peeling of the skin, and if the skin is exposed to a strong ultraviolet environment for a long time, it will also increase the prevalence of skin cancer, so it is not recommended to sunbathe casually. Therefore, it is not recommended to sunbathe casually. It is recommended that patients diagnosed with cancer should go to the hospital for standardized treatment in time, and improve the prognosis by treating the disease before it is too late.