What are some tips for teens about health?

health is pretty broad but since this is diet and fitness, eat well, excercise often

dont smoke or drink

Balanced diet of fruits, veggies, grains, etc. Exercise regularly, get plenty of sleep. [:

stay away from sugar if u start to read the ingredients of the food u eat u will be amazed at the amount of sugar some stuff has in it like milk. Don't drink soda or coffee

Health regarding what topic?
There are lots of things teens should be aware of in their growing bodies.
First, they are still growing. They need to insure they get addequate sleep and nutrition. They should NOT diet (unless their doctor deems them overweight and places them on a diet).
They should avoid aclohol and tobacco use, as well as illegal drugs, and they should be warned of the effects of these.
Teens should avoid sex, or be cautioned of STDs and provided with condoms. Teens are defiant, and are going to do what they want. All you can do is provide them with information and means to protect themselves.
I hope I have helped. If I have missed anything specific that you want information on, send me a message!