Nope you will start burning muscle.
The thing is pure fat burning doesnt even begin until the 20min mark at 65%. so bump it up to 45 or even better 60mins. You will notice fat come off each week around 2 pounds.
If your loosing a lot more weight then take it down a notch because the body can only loose that much fat each week without turning on muscle for energy.
I do cardio around 4 times ew min. when trying to loose fat.