Shaving the armpits does not usually cause bad odor, which may be related to the parietal sweat glands, genetic factors, environmental factors, dietary habits and other reasons. 1. parietal sweat glands: the secretions of parietal sweat glands may produce ammonia and unsaturated fatty acids with the bacteria that colonize the skin of the underarms, thus leading to the appearance of odor in the underarms. 2. Genetic factors: Fox odor is hereditary, and if the parents suffer from it, the chances of the next generation suffering from the disease will increase. 3. Environmental factors: If the weather temperature is high, it will make the body sweat more, which may induce or aggravate the fox odor. 4. Dietary habits: If you often consume oily and spicy food, it may also induce the disease. At present, there is no clinical evidence to prove that shaving armpit hair will lead to bad breath, if bad breath occurs, it is recommended to go to a regular medical institution, scientific and standardized treatment.