Losing weight is really a balance of calories in, calories out. To slim down, you simply have to create a calorie deficit, and this is how to find your magic diet number: First, calculate how many calories you burn in a day. (Try websites like Calories Per Hour, FitDay, CalorieCount, or BMR Calculator.) My results varied, but the lowest figure I found said I burn 2,298 calories a day. If I want to lose 1 pound a week, I need to create a calorie deficit of 3,500 to 5,250 calories a week. To do that, I’m cutting 600 calories a day from what I eat, or limiting myself to 1,698 calories a day.
If I want to lose 1.5 pounds a week, I need to cut or burn an extra 1,050 calories—in addition to the calorie-cutting above. This is where exercise comes in. Using an activity calculator, I discovered I burn about 270 calories on my short walks (for me, that’s a 40- to 45-minute walk). If I walk four days a week at 3.5 mph, I’m covered.
I've stuck to this method, and I've lost more than 30 pounds. It may be slow, but it's a healthy way for me to get to my ideal body.