The reason for the old acne is overwhelmingly related to the following aspects: 1, hormone level secretion is more vigorous: so the people who have acne are generally more adolescents. 2, sebaceous glands secretion is more vigorous: that is to say, more oil, water and oil imbalance is very easy to grow acne. Because oil is a good medium for acne bacteria, live better. 3, infection of acne bacteria. 4, bad habits: there is a very important, that is, bad habits of life and living, such as diet and staying up late, these are very important, there is also a willingness to smoke, drink alcohol, these are very important a cause. The first thing to do is to avoid spicy, sweet and fried foods, and to apply a mask to regulate the balance of water and oil. The other thing is to stay up less, reduce the frequency of smoking and drinking, and improve your lifestyle is very important.