Hello There,
Im being sarcastic of course. Cardio is exercise and exercise burns calories. Weight = calories, so if you exercise cardio or otherwise, you get fit and lose weight. That's oversimplified I know....What I think you heard is that cardio might not be the most optimal or best-suited choice of exercise to lose weight because there a debate does exists.
Read up on this article..It's not comprehensive, but it explains alot.
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