A better method
The above example shows us that setting caloric intake relative to bodyweight (or by
creating a deficit as some percentage of maintenance levels) would be more individualized than
using an absolute deficit (such as 1000 calories below maintenance) or an absolute caloric intake
(such as 1200 calories per day).
The method recommended in this book is to set caloric intake relative to either bodyweight
or maintenance levels. It assumes that maintenance calories have either been determined with
a food diary, or estimated from the equations in section 2. It also assumes that the total caloric
deficit includes exercise. For a 500 calorie/day deficit, whether an individual reduces food intake
by 250 cal/day and increases activity by 250 cal/day or eats at maintenance and increases
activity by 500 cal/day, the deficit will be considered to be the same. Note that this only applies
as long as some form of exercise is being done as numerous studies have found that reducing
caloric intake without exercise causes muscle loss and a drop in metabolic rate.
When starting a fat loss diet, calorie levels should be restricted no more than 10-20% below
maintenance levels. This caloric deficit can be generated by decreasing food intake or increasing
activity with exercise. While the typical recommendation for increasing caloric expenditure is
aerobic exercise, we shall see in chapter 22 that weight training coupled with either aerobic
exercise OR a slight reduction in caloric intake yields the best fat loss. For all practical purposes,
there is no difference between reducing calories by 300 per day and expending an additional 300
calories through aerobic exercise. The choice ultimately becomes the dieter’s: whether to eat less
or perform more aerobic exercise. It is the opinion of this author that weight training is NOT
optional on any diet.
From a maintenance level of 15-16 calories per pound, reducing calorie levels by 20% yields
a calorie intake of approximately 12-13 calories per pound of current bodyweight. Many diet
books and dieters prefer to use a caloric goal based on goal bodyweight (i.e. 12-13 calories per
pound of desired bodyweight). The problem with this method is that dieters, in their hurry to
reach their goals, invariably set goal bodyweight or bodyfat far too low. Consequently, calories
are set too low and metabolic rate slows down. Therefore, daily calorie levels should be based on
current bodyweight.
Using the values for maintenance calories from the last section we have:
Female at 150 lbs 15 cal/lb = 2250 cal/day
A 20% deficit yields 2250 0.20 = 450 calorie/day deficit
2250 calories - 450 calories = 1800 calories per day
1800 calories/day / 150 lbs = 12 calories/lb
Male at 180 lbs 16 cal/lb = 2880 cal/day
A 20% deficit yields 2880 cal/day 0.20 = 576 cal/day
2880 cal - 576 cal = 2304 cal/day
2304 cal/day / 180 lbs = ~13 calories/lb
These levels should be considered starting points only as they are based on averages and
estimations for maintenance calorie levels. Some individuals may need to reduce calories further
but this should be done cautiously to avoid muscle loss and metabolic slowdown.