问:我儿子七岁,现在二年级,咬指甲有半年了,指甲总是秃秃的,有时还被他咬出血。我们带她去过省级儿童医院,医生说是焦虑或缺锌。回来后补过一段时间,大概有一个月,后来感冒咳嗽,就没再坚持补。症状持续到现在。孩子很聪明懂事,学习成绩优异,平时也比较开朗,语言表达能力强,爱读课外书。我想可能也不 Q: My son is seven and now second-grade, biting nails for half a year, nails are always bald, and sometimes he bites bleeding. We took her to the Provincial Children’s Hospital, and the doctor said it was anxiety or lack of zinc. After a while back up some time, about a month later cough cold, no longer insist on making up. Symptoms persist until now. Children are smart and sensible, excellent academic performance, usually more cheerful, strong language skills, love to read extra-curricular books. I think maybe not