Vocal change usually occurs during puberty, but the timing of vocal change varies according to gender, and there are also differences between individuals. It is a very important time for the development of the vocal cords, so it is important to take advantage of this time and take some measures to protect the vocal cords to avoid affecting the normal development of the vocal cords. 1. Boys: The period of voice change is around 12 to 15 years old, do not use your voice excessively at this age. Adolescent boys like to yell and scream to express their dissatisfaction, which can easily lead to congestion of the vocal cords, and your voice may remain hoarse in the future. 2. Girls: The period of voice change is around 12 to 14 years old, during this period, we should avoid stimulating food: cold, sour and spicy food can easily cause irritation to the throat, vocal cords and other vocal structures, which in turn affects their normal development, and girls in the period of voice change should eat more nutritious and light food. Vocal change is usually in adolescence, there are differences between individuals, is a very important stage in the process of growth, whether it is a vocal change or non-vocal change, should not be excessive use of the voice. If you have any doubts or concerns about voice change, you can seek advice from your doctor.