What diest should i follow to reduce 30kgs in 4 months. i weigh 120 kgs, height 183cms and 23 years of age.

Diet slowly. See Dr.: Helpful weight loss diets have natural foods that take time to chew but contain few calories. Examples include carrots, celery, and iceberg lettuce (little/no salad dressing). When shopping for fruits, buy small ones no bigger than a tennis ball, because fruits have sugar. Drinks without calories include water and green tea. A calorie is a calorie, but surely avoid sugar & simple starch calories.

Your goal weight : loss rate is too steep to be healthy. Try setting goal for 1 up to max of 2 lbs per week average. Insure that calories burned > calories consumed. Drink at least 8 - 8 oz glasses of water /day. Aim for 8 hrs of sleep & at least 5 servings of vegetables & 4 of fruit /day. Use whole grain when possible. Avoid soda, alcohol & junk carbs. Get mix of cardio & weight lifting exercises.