Whether or not it is normal for a 19-year-old to jerk off once a day needs to be judged by whether or not there are physical symptoms after masturbation. If once a day, but does not affect the next erection, and there is no genital and physical discomfort, then there is no need to worry, moderately reduce the frequency and maintain cleanliness and healthy habits. However, if after masturbation, there are symptoms such as reduced erectile hardness, reduced ejaculation strength, reduced semen quality, mental weakness, fatigue and weakness, then it is excessive masturbation, which is harmful to the body and may even lead to prostatitis, erectile dysfunction, premature ejaculation and other diseases. Even if this happens once a month masturbation, it is still excessive masturbation. Therefore, for a 19-year-old young man who has just finished his puberty, it is important to masturbate moderately, avoid excessive masturbation, and do a good job of cleanliness and hygiene.