The sound quality is determined by the vocal cords. Vocal cords are a pair of elastic mucosal folds located on both sides of laryngeal cavity, and their length and thickness vary from person to person. In childhood, male and female vocal cords are 6 ~ 8 mm long, so the voice is children's voice, and children's voice can't tell men from women. Teenagers begin to change their voices at the age of 14 ~ 16. The main manifestations are hoarseness, local hemorrhage and edema, and gradual change of timbre. Generally, it takes half a year to 1 year to complete the voice change period. Adult men have a thick and deep voice and a wide and thick volume, which is closely related to the thickness, width and length (about 20 ~ 25mm) of their vocal cords. The shrill whispers of adult women are related to the narrowness, thinness and length of vocal cords (15 ~ 20mm). It can be seen that the timbre difference between men and women is particularly obvious after the voice change. In order to ensure a good voice during the voice change period, we should emphasize diet conditioning.

Pay attention to the intake of collagen and elastin. Because the vocal organs are mainly composed of Adam's apple, Adam's apple and thyroid cartilage, these organs are composed of collagen and elastin. Vocal cords are also made of elastin membrane, so teenagers in voice change period should eat more foods rich in collagen and elastin, such as pig's trotters, pig's skin and pork tendons.

You should eat foods rich in vitamin B and calcium. Vitamins B2 and B6 can promote the development of skin and sound. Calcium can promote the development of thyroid cartilage.

Eat less or don't eat spicy food, such as pepper, garlic, pepper, tobacco and alcohol, so as not to stimulate vocal cord mucosa and cause acute and chronic laryngitis and pharyngitis.

Pay attention to eating slowly and avoid wolfing down. Especially when eating fish, you should pay more attention to prevent the fish from stinging your throat. And you should eat some soft food and fine food, not rough, hard and dry food to avoid hurting your throat.

Drink water in moderation. It can reduce or clear the secretion of laryngeal cavity, thus reducing the growth of bacteria. Conducive to the prevention of pharyngitis.

In addition, don't be loud, tired or lack of sleep during the voice change period, and don't cause mood swings to prevent throat congestion and vocal cord damage.