Girls’ breast development should consult endocrinology or growth and development department. When a girl’s breasts start to develop, it indicates the appearance of secondary sexual characteristics, which is a normal manifestation of puberty. Generally, girls’ breasts start to develop at the age of 10-11 years old. If a girl’s breasts develop before the age of 10, it is usually considered to be a sign of precocious puberty, and it is recommended that she go to a regular children’s hospital and register with an endocrinologist or growth and development department as soon as possible for examination and evaluation. When a girl reaches the stage of breast development, her diet structure must be reasonable, to ensure a balanced diet and nutrition, and usually eat more food containing high-quality protein, such as beef, mutton, milk, eggs and so on. If the examination reveals precocious puberty, the diet should be adjusted in time to avoid foods containing hormones.