Many people say that French fries, hamburgers, chicken legs and wings from KFC and McDonald's are junk food, which is unhealthy in nutrition. Why is that, isn't it?

I worked part-time in it. To tell the truth, the meat inside is frozen. I've read a report before that those chickens were all made in a few months, which may be useful with hormones and so on. The oil used for fried chicken is changed once a week. In fact, it's ok to eat those things occasionally, but it's not good to eat them often. Please adopt them!