I am 24 and weigh 88 kgs. i have tried dieting with regular walk in morning and 20 minutes exercise in evening. but no results.please suggest.

Change something: It sounds like you are in a rut. Time to change what you are doing. A different exercise routine or at a different time of day if possible. Pay careful attention to the portion size of your diet. Try cutting out one type of food, like bread, rice or potatoes. You didn't mention your height so no way to know what is ideal for you. This approach worked for me. Good luck.

Overweight: Read this first for inspiration and motivation: http://www.Surgeongeneral.Gov/library/calls/obesity/fact_whatcanyoudo.Html. This is the time to tackle the problem aggressively. Meet with your doctor and a nutritionist and MAP out a plan for you. Stick to it. Don't let it get you down. Calorie control combined with exercise is the key. Bariatric surgery might be in your future, but start w/ your md.