I know how it works with calories, you eat too few your body starts to eat away at fat reserves but you need about 2000 a day to maintain weight and around 1500 a day you’ll lose about a pound a week but how do people lose more weight than that while doing very little or no exercise? And how does exercise help any how? You only burn 100 calories every mile you run/walk and 3500 calories is a pound. Unless you run/walk tens of miles a day along with the fewer calories you shouldn’t be losing much weight. Take me for example. I eat around 1000 calories a day and walk only 5 miles daily. That’s about 2 ounces lost and to make thing easier we will say 1000 calories is 2 pounds a week which is about another 2 ounces so 4 ounces a day so it should be a pound in 4 day but how is it I’m losing around a half pound a day, 2 pounds in 4 days? I’m losing the weight in 1/2 of the time. So what else is my body doing to burn off these extra 875 calories a day on its own?