There are many things you can do to stay healthy and fit. I'll give you a list of what I do. Not everyone will agree or will be able to do all the things I do. But here goes
First diet. I lost 36 lbs. and went from 214 to 178. It was a combination of South Beach and Mediterranean. And eating out more at home vs going out. I actually eat more bread now but it's either Multi grain or a Whole Wheat Sourdough.
Exercise is very important. I exercise three times a week. I use light weights and some aerobic type exercises. Also walking is very important. I walk twice a day for 30 and 15 minutes. If you have a exercise bike does that.
Finally, I eat a lot of fruits and vegetables. I also take a multi vitamin that has C, D, and E. plus zinc and iron. I have held my weight this past year and when I enter my 70th year tomorrow I look forward to a continued healthy year.
You only have one life here.