.I reach home by 7.15 and then i have to cook for the next day. So i feel very tired to do excercise. please help me

Nourish your body thin, instead of starving your body fat. Good carbs like celery and carrots will never make you fat. Bad carbs like cake will, but you don't need to know the whole science of glycemic load. You need to re-learn how to eat so you can become thin and healthy. Salt has no calories but makes you fat and burning more calories does not help this fatness.
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You can force your body to lose weight with not enough calories, but if you continue it, you will starve to death. With an abundance of healthy foods, you lose weight just as fast, but only until you reach your ideal weight. You can continue eating this way the rest of your life and always be at your ideal weight.
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All the fiber rich foods will help, green leafy veggies, green beans, asparagus, broccoli. All of these will help, but you probably won't lose any weight without at least a little exercise. Stay away from all sodas and drink lots and lots of water!

There has been a range of food diets, from green tea to Oprahs staying away from 'white ' foods to etc etc. I am glad you are talking friuts and veggies, so you got that right. these don't have fats which are fattening, but however have carbohydrates which can bond to form longer starch chains which are stored as fat. So stay away from potatoes sweet or otherwise.