Why People Gain Weight

Excess Calories (meaning food energy) are what put on weight.

But dietary fat, carbohydrate, protein, and other nutrients strongly affect this process in ways that can make weight loss either easy or nearly impossible.

In this section we discuss:

Why simply limiting excess calories will not -- by itself -- make you lose the weight.

How many Calories you really need. You actually can know this with a lot of precision.

How many Calories can you reasonably cut out in order to use up stored fat?  There are several practical limits and even a few theoretical limits.

How long will it take?

What problems will you run into as you do this?

Main Discussion:
Calories do count!

Calories measure a vital nutrient -- food energy -- which your body must have in order to survive.

But excess Calories make you fat. In other words, too much of a good thing ... is not a good thing.

Actually, Calories are so vital to your survival that your body is genetically "hard-wired" to "play it safe" by storing every Calorie it doesn't need to use right away -- "just in case it might need them during the next famine...". And your body has a nearly unlimited capacity to store excess Calories. (In contrast, every other human nutrient has a very limited storage capacity.)

Nor can your body waste any of this vital nutrient -- either before or after it's been stored -- because it has no way to "flush out" Calories without burning them or to burn them without first needing the energy to keep you alive & move you around.

That's the bad news. But this bad news becomes irrelevant when you understand it and know how to work around it.

The good news is that your body pulls excess Calories out of it's fat stores just as easily as it puts them in.

Many people (including professionals), assume -- wrongly -- that your body can easily store Calories but can't easily get them back out of storage when it needs them (like when you're on a diet). This is wrong. God & evolution don't work that way.

In fact, fat cells routinely release fat into your blood every minute of every day because your muscles and muscular organs like the heart routinely use mostly fat for energy.

In other words, fat does not somehow "get stuck" in your fat cells.

Then why are diets so hard?

Dieting becomes difficult only when it causes sensations like hunger, cravings, aches, pains, and low energy levels.

But these sensations have nothing to do with how many Calories you eat or how fat you are. They are caused entirely by other food factors.

In other words, Calories do not control hunger. And that's good, because it means it's possible to eat very few Calories, and therefore use up stored fat for energy, but still not feel hunger, simply by also properly managing the other food factors that actually do control hunger.

So Calories do count and must be controlled. But limiting Calories does not make diets difficult. Then what does make them difficult?

Diet difficulty is caused by the other nutrients in food, and to eliminate it while you are losing weight, they must also be controlled.

Calories are just one of the roughly 50 nutrients your body needs to get from food and in the right amounts in order to be healthy. Whenever your body starts to run low on even one of these nutrients it will trigger a vague "food focus" that will quickly grow into the very unpleasant sensations of hunger, cravings, aches, pains, and low energy levels.

In other words, it wants you to eat food to get it more of whatever nutrient it needs. You've almost certainly experienced this many times.

But go look in a mirror. Does it look like you're running low on stored Calories?

If not, then these unpleasant sensations must be caused by your body getting low on one of the other nutrients it needs from food.

So in addition to limiting calories, you must make sure you also get enough of all of the other nutrients your body needs.

The very best news we can give you is that these other factors are also simple to control -- once you've learned how and practiced the technique a little.

In other sections of this website we discuss these other factors and how to control them properly.

In the rest of this section we talk about Calories and their effect on body weight. How many Calories do you need? How many can you reasonably cut out in order to use up storage fat? How long will it take? What are the problems you're likely to encounter as you do this? See How Much Should You Weight?

The Body Mass Index

Another useful number to know is your Body Mass Index (BMI). BMI is a formula that gives approximately the same results as the desirable weight table.[1]

However, the BMI (Body Mass Index) extends the value of the IBW tables by allowing a determination of how much overweight you are compared to other people of different heights. In other words, a BMI of (e.g.) 25 represents approximately the same degree of body fatness in a person 5’2” (157 cm) as it does in a person who is 6’2” (188 cm) or any other height.

How accurate is the BMI? When tested against the underwater weighing technique (which is considered to be very accurate), it shows a high degree of correlation. But obviously no general formula can account for all individual variation.

The BMI formula is most accurate in adults between 19 and 70 years of age. It is less accurate in competitive athletes and body builders (i.e., people with a large muscle mass). It is also less accurate in women who are pregnant. The BMI is not useful for growing children or in elderly patients who are both frail and sedentary.

The Body Mass Index (BMI) is becoming the standard scientific way of talking about obesity for two reasons:

1. It is an easy way to compare the body fat level of people of different heights.
2. When researchers know this body fat level they can more easily connect it to the person’s general level of health and to specific diseases likely to develop.

The mid-point of the desirable weight range for each height on the Metropolitan Desirable Weight Table falls at a BMI of between 21 and 22. In other words, a BMI of 21–22 probably represents your “ideal” (i.e., healthiest), weight.

The 1998 reclassification of terms by the National Institutes of Health (U.S.) now defines a BMI of 25 or higher as “overweight” and a BMI of 30 or higher as “obese”. This means that clinically observable health problems typically begin to emerge when BMI rises over 25.

Calculating Your BMI (Metric System)

If you would like to know your BMI, you can calculate it most directly using the formula BMI=Kg/M². That is, BMI = your weight in kilograms divided by your height in meters squared. (You’ll need a calculator).

Calculating Your BMI (English System)

For Americans and others who typically use traditional English measurements instead of the metric system, the following is a mathematical adaptation of the above metric formula. (You’ll still need a calculator.)

To calculate your BMI:

(1) multiply your weight in pounds by 703.

(2) Divide the number you got in step 1 by your height in inches.

(3) Divide the number you got in step 2 by your height in inches again. The result is your BMI.

If you don’t like formulas or don’t have a calculator handy, the four BMI tables below will make your life easier.

To use these tables:

(1) Select the table that contains both your height and your weight in the heading.

(2) From the first column, select the row with your height.

(3) Then find the column in that row that contains your weight.

(4) Then look at the bottom of that column to find your BMI.

See also Why is BMI Important?andHow Many Calories Should You Eat Daily in Order to Lose Weight?

Activity Energy Expenditure (AEE)

Your AEE (activity energy expenditure) is normally the second largest component of your total energy expenditure. This is the amount of energy in addition to your REE that you expend by moving around and doing things.

The energy expended during many different types of activity has been measured and summarized into five categories called “activity levels”, for which numerical activity factors have been calculated.

Activity Levels

Estimate your average daily physical activity level by using the following definitions:

• Resting Level: Sleeping, reclining.
• Very Light Level: Seated and standing activities, painting trades, driving, lab work, typing, sewing, ironing, cooking, playing cards, playing a musical instrument.
• Light Level: Walking on a level surface at 2.5–3.0 mph, garage work, electrical trades, carpentry, restaurant trades, house-cleaning, child care, golf, sailing, table tennis.
• Moderate Level: Walking at 3.5–4.0 mph, weeding and hoeing, carrying a load, cycling, skiing, tennis, dancing.
• Heavy Level: Walking with a load uphill, tree chopping, heavy manual digging, climbing, basketball, football, soccer, etc.

(Note that if you really want to be sophisticated, you can record the number of hours each day that you do each of the above types of activities and calculate an average level to use in the tables below. This is probably a bit more effort than most people will want to bother with, however. )

1. Multiply your REE by your Activity Factor to get the approximate number of Calories of energy you expend moving around every day. 
2. Add this number to your REE to get a total.

Total Energy Expenditure (TEE)

In 1985 the World Health Organization (WHO) defined the energy requirement for individuals as:

“...that level of energy intake from food which will balance energy expenditure when the individual has a body size and composition, and level of physical activity, consistent with long-term good health; and which will allow for the maintenance of economically necessary and socially desirable physical activity.”

Ick! What incomprehensible“ bureaucratese!”. Who writes this stuff? (Ok, it’s accurate, but what does it mean?)

Basically it just means the Total Energy Expenditure (TEE) of a normal person who is neither gaining nor losing weight. (Why couldn’t they just say that?J) This Total Energy Expenditure (in Calories) is mainly the sum of your Resting Energy Expenditure (REE) and your Activity Energy Expenditure (AEE). Table 8 & Table 9 below will give you a good idea of how many calories it is for you. Obviously if you eat fewer Calories than this number you will lose weight (the fewer, the faster)—and that’s the reason you need to know what it is.

To find your TEE using the tables below,

1.Find your usual daily activity level in column one.

2.Write your REE in column 2.

3.Multiply by the activity factor in column 3.

4.Write the number you get in column 4

5.This is your “normal” TEE. You need to know this. We will be using it shortly to make a realistic calculation of how fast you can actually expect to lose fat (assuming you can handle the Eight Vital Factors properly).

How Fast Can You Lose Weight?

Deciding on Your Daily Calorie Limit

Once you know your TEE from the tables you can decide how much of an energy deficit it is reasonable for you to create. This will determine how fast you lose weight.

One pound of fat is 3500 stored Calories, so to lose that pound, 3500 Calories is the deficit you must create over some period of time. If you want to lose one pound of fat per week, you will need to create a 500 Calorie deficit per day (3500 Calories ÷ 7 days = 500 Calories per day). To lose two pounds of fat per week, you double this number and create a 1000 Calorie per day deficit (1000 Calories x 7 days = 7000 Calories lost (¸ 2 = 3500, or 2 lbs)).

In other words, subtract 500 Calories from the TEE you calculated in Table 8 or Table 9above and you will lose one pound per week. Subtract 1000 Calories and you will lose two pounds per week. Simple!J

However, for safety reasons you must not subtract so much that you eat less than 1200 Calories per day.

Table 10below will help you apply appropriate calorie deficits to your own situation to determine your proper Daily Calorie Limit.

Strict maintenance of this Daily Calorie Limit is the way you stay off the Liar’s Diet. (And strict control of the Eight Vital Factors, as we discuss starting in the next chapter, is the way to stay off an ineffective, unpleasant "Heroic" Diet

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