We are genetically programmed to eat until the sensation of “fullness” sets in—a complex response involving blood sugar levels, brain chemicals, and other biological factors, aided by tiny “stretch receptors” in the stomach that signal the brain when its capacity has been reached. The human stomach is a pouch about the size of a clenched fist. Most people assume it to be larger, but normally it isn’t. However, the stomach will stretch in size if we continually cram it with food. When this happens, the stomach requires ever-increasing amounts of food to trigger the stretch receptors that signal fullness. But this overeating isn’t the main reason we become overweight, because it isn’t how much food we pack into our stomachs that causes the problem, but rather the kind of food. Calories, not the volume, are the real culprit. This is an important distinction, and understanding it is the single most important key to controlling your weight, or slimming down.
Ounce for ounce, modern processed foods contain far more calories than anything found in nature. They are loaded with extra fat, which contains more than twice as many calories per gram as carbohydrates and protein. Many commercial foods also contain added sweeteners in the form of high-fructose corn syrup, a highly concentrated source of calories. We also eat loads of refined, calorie-dense carbohydrates such as breads, cookies, cakes, crackers, and candies, to name just a few of the popular foods that pack an enormous amount of calories into a few bites.
One of the most extreme examples of these calorie concentrated foods is what we have come to call fast food a greasy hamburger topped with cheese, slathered with mayonnaise-based sauce, and sandwiched between a big bread bun. This is a meal unto itself; but it is frequently served with a side of deep-fat-fried french fries and a soft drink that can contain the equivalent of 40 teaspoons of sugar.
By the time your stomach signals it is full from the physical volume of one of these calorie-intense meals, you could have easily consumed 1,200 calories or more. This is nearly twice as many calories as the body can put to immediate use, so the excess is converted into fat and stored away in your fat cells. Just one meal like this contains nearly all the calories needed by the average female, whose intake shouldn’t exceed 1,800 calories per day if she doesn’t want to gain weight.
Add to this a breakfast, a sit-down dinner, a few snacks, and another soft drink or two or three, and it’s easy to see the enormous impact that a simple fast-food lunch can have on your weight and, ultimately, your health.
So here we are, surrounded by an unprecedented abundance of food that is more concentrated in calories than anything humans have ever known. To make matters worse, we are conditioned to eat three meals a day. “Three squares a day” was a necessity back in the days when our forefathers were hardworking farm families. Back then, the average man and woman labored from sunrise to sunset—the equivalent of running ten miles a day—requiring as many as 5,000 calories a day.
