Rule Basics

Breakfast, lunch and dinner should each have about 1/3 of your total daily calories. To determine how many daily calories you need you first need to calculate your basal metabolic rate. In order to do that you need to know 4 things: your age, your sex, your weight and your height. There are many basal metabolic rate calculators on the internet. A good one is at Discovery Health.

Once you have your basal metabolic rate you next need to establish a caloric deficit. We recommend a weight loss of 1 pound a week. Each pound of fat produces 3500 calories when burned so to lose a pound a week you need to have a 500 calorie a day deficit. So subtract 500 calories from your basal metabolic rate and this is your total daily calorie intake for weight loss. Divide this number by three to figure how many calories per meal you can have. You then need to eat this number of calories (+/- 50 calories per meal or so) with each meal every day.

If your calculations come out below 400 calories per meal then round up to 400 calories per meal. You will need to make up the difference in calorie deficit through exercise. In other words if you calculations come out at 350 calories per meal, then that is 50 calories less than 400. You need to eat 400 calories per meal but you will also need to exercise for 150 calories per day to make up the difference.

If your calculations come out above 700 calories per meal then round down to 700 calories per meal. This is because the equation to calculate basal metabolic rate is based mainly on lean body mass. If you are severely overweight (BMI>45) then the equation will overestimate your basal metabolic rate by as much as 30%.

The number of calories in a meal can not be estimated. We are usually off by as much as 100% in our estimation of the number of calories we take in. You need to measure and record every calorie. At least for the first month this needs to be an absolute rule. By then you will have seen 2 dozen breakfasts, 2 dozen lunches and 2 dozen dinners and have a much better idea about what portion size actually corresponds to the number of calories you need to have per meal.

Reasoning Behind the Rule

The first law of thermodynamics states that energy can not be destroyed or created, only transferred. Since fat is essentially energy, the only way to get rid of the fat is to transfer it out of the body. This means that you have to use up more calories than you take in, or in other terms, to create a calorie deficit.

If you don't balance the calories across the day you will not get satisfactory ghrelin suppression between meals. As a result you won't maximize your metabolic rate. You will also be much more likely to get hungry and therefore have more difficulty maintaining the calorie deficit you need to achieve weight loss.

As far as the breakdown of the composition of each meal as to how much should be carbohydrates versus protein versus fat, your hunger patterns will determine the distribution. For more details see Rule 3.Each person will have a different breakdown depending on how their hormonal systems work.

After each 20 pounds of weight loss you need to recalculate the formulas and get a new total daily calorie limit. Once you have reached your goal weight and your BMI is in a healthy range, you can adjust the total daily calorie limit to maintenance levels as opposed to weight loss levels. To do this simply do not subtract the 500 calories per day so that you don't end up with any calorie deficit.