Dr. Chokaew Kongkha, M.D. Chamnankan Head of Endocrinology Queen Sirikit National Institute of Child Health confirmed to Hfocus that drinking milk and eating chicken does not cause premature puberty But it can temporarily cause secondary sexual characteristics, such as estrogen, causing the breasts to temporarily rise. But when I stop consuming breast milk, it will disappear on its own. As for girls who are pre-teens, it can be caused by 2 reasons: the brain commands and not. mostly found in girls Some people will have brain lesions as a trigger. or have abnormal genes