Why do they say to cut carbs?

Aren't carbohydrates what give u energy? So why do people say to cut them out when u diet to lose weight?
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+1 y
I workout at the gym so should I cut them out? My trainer told me its a good idea. I am not overweight at all though.
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I am trying to lose more weigght though so could that be it? Do carbs stop weight loss?
Why do they say to cut carbs?
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