What do you want to say about this subject? Should people ever eat junk food? How much is appropriate? Why shouldn't they eat junk food? Or should they eat junk food? What kinds of junk food are healthier? Or are there any healthy junk foods?
Think through the answers to these questions -- and any other questions. Read through this article.
Write down your thoughts. After you've done that, you'll have a much better idea for formulating a thesis statement.
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