having unhealthy nutrition among people ...
Well, I think I need to rewrite your intro, since some ideas did not fully cover what should be in the opening paragraph.
Today's issue is how to maintain people health. This notion is utterly true, since many people live under poor health conditions. Lack of exercise and eating junk food can be the reason why this issue is growing. To tackle this matter, I believe that people should be encouraged to take regular exercise and eat healthy food.When it comes to the introduction, I always break down my strategy intro three steps.
1. A Hook., a catchy phrase. Such a phrase can attract readers attention.
2. Background information: simply restate the question.
3. Thesis statement + Outline: Here you need to show your claim regarding the issue, and then prove it with an outline, as the main topic of discussion.
Hope this helps :D