Christianity is one view of the world, just like Judaism and Hinduism. It will always insult someone, just like every religion will. There will always be something in a religion that not everyone will agree with. Yes, religion is man-made, just like god and any other supernatural creation. Eventually, Christianity will die out, just like paganism and polytheism, and some new-fangled religion will take the world[s] by storm. So to summarize, yes, it is healthy to believe in Christianity because Christianity is one person's belief and we all have our own right to believe what we want.
If one must choose a religious stance, Christianity is not a bad way to go. It is based on strong ethics that are generally accepted by society and in some ways has a positive influence on the way we live. For example, Christianity is family-focused, which is one thing not necessarily promoted by other world religions.
Christian values, such as abstinence from sex until marriage and abstinence from alcohol, are quite healthy. It also provides a standard of right and wrong. Extreme Christianity is not healthy, but Christianity in general is healthy.
However, though it is healthy it can be dangerous to your health. For instance, if you're a Christian in a Muslim country you'll quite possibly get killed by a violent mob.
It is healthy to have faith in God just as long as you aren't forcing it upon other people, for example, it is NOT healthy to join an extremist church, like Westboro Baptist Church, that stalks certain people and terrorizes them because they don't do exactly what they say, but having faith is very healthy.
The common misconception about Christianity is that it is a religion, it is not, it is a true relationship with God and accepting Jesus as your saviour. As a Christian I can honestly say that Jesus hated religion, he is not a religious man, He is our savior. So yes it is very healthy to believe in Christianity and be a follower of Jesus.
Practicing many Christian values is healthy, but does it necessarily follow that believing, loving, and trusting in a God that is jealous of the worship of any other God (Old Testament), asks for you to always forgive or ignore harm that is done to you (New Testament), asks that you harm yourself or loved ones to prove loyalty to God (Old Testament), asks that you sacrifice everything for a stranger on the premise that the stranger is always the needy and you are not even if you were to starve to feed them because you have something they do not you are obligated to share (New Testament). The right exists to worship whatever anyone believes and should not be taken away. It is not healthy to believe all that, it is even more unhealthy to believe that someone who doesn't work for my food, and shelter should have the right to it because he has none for himself. While it is a pretty ideal since no one with any feeling wants anyone to starve, when someone is unwilling although perfectly capable of working for the same things and as a result has nothing should not in turn deserve my hard earned food, shelter, and luxury just because he has none.
I've seen people say that ethics is something religion teaches, but threatening them with the wrath of a god is not teaching them about ethics. That only teaches them about the wrath of god. Teaching ethics requires teaching a person about themselves. Does the person like to have things stolen from them? Does the person like the idea of being killed or injured? Does the person like to feel bad? Nobody really does. Knowing this that person will able to see a certain part of themselves in another person that does not want these bad things to happen.
Could you believe that atheism is the most distrusted view out there? Some people actually question "How does an atheist have morals?" and then they don't seek for the answer. They stop right there and assume atheists have no morals because they don't know the wrath of God. They confuse wrath with ethics and it is kind of scary.
It insults our integrity by saying we are all sinners who must accept a human sacrifice to appease an angry god and terrifies children with threats of hell. The divisiveness separates families, cultures and nations in an attempt to uphold ancient superstitions. Luckily we have no good reason to think it's true.
No I do not believe that Christianity is a healthy thing to believe in. I have difficulty finding so much stock put solely into a book which was written so long ago. Also I have serious issue with their view on women and don't think that is is healthy for young girls to be brought up that way.