Excess of everything is bad. If you want to reduce yourself, you should have a balanced approach between the two.
Best way to reduce the weight is to consult some good nutrition first and have proper diet plan. In this way you will be able to reduce you weight without having side effects.
Nutrition will give you proper plan for diet and some basic exercises. By following that you can reduce you weight.
So in the end, some fasting with proper workout will help you out in achieving the desired result.