Jaw acne may be caused by overdeveloped sebaceous glands, endocrine disorders, digestive problems and other factors. 1. Sebaceous glands are too developed: chin acne is caused by overdevelopment of sebaceous glands and excessive sebum secretion. 2. Endocrine disorders: long-term late night, fatigue, tension, anxiety, irregular diet, etc., can easily cause endocrine disorders and hormone level disorders in the body, which can lead to sebaceous gland secretion, a large amount of sebum is blocked in the mouth of the hair follicle, easy to grow acne. 3. Digestive problems: such as constipation, chronic diarrhea, excessive stomach acid, ulcers, etc., will lead to the accumulation of toxins in the body, the waste can not be discharged properly, at this time, the digestive system reflective jaw area around the acne will also appear. Pimples appear in the jaw.