Turn down my frined's cholesterol level

My friend went to the doctor and discovered who his cholesterol level is high. I decide help he and start to take care about my own cholesterol level. I encouraged my friend to do some exercises with me, and we will start to go to the gym. Meanwhile, we decided to go walking to our jobs. He every time eats fat foods like pizza and hamburgers, but now I will lunch with him to see if his diet changed like the doctor suggested, and to encourage him to drink more juice, to eat more fresh fruits and vegetables. Also, at job he has a lot of stress trying to solve the many math problems, he is a engineer. We will start yoga classes next week. Finally, I saw that help my friend with his health will help my health too.