It's the Calories, Stupid!

By Terry Dunkle, DietPower Editor-in-Chief

One recent afternoon, while sunning on the Maine coast, I overheard a lot of talk about diets. A girl on a neighboring blanket asked her boyfriend, "What's this whatchacallit 'beach' diet the Clintons are on?" Two women a little too old for their bikinis walked by, discussing the evils of white bread. A retiree with a potbelly as big as the nose of a B-17 told his Frisbee partner that he was thinking of "going on Atkins." A talk-radio caller waxed enthusiastic about the Blood Type diet.

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After 30 years of covering science and health for newspapers, magazines, and websites, I'm a little tired of hearing this stuff. If you really want the best diet for yourself, you don't choose it on the basis of a tabloid headline, a TV commercial, or a guy with a microphone who says he's a doctor. You ask someone you can trust—someone who knows the difference between a fact and a claim, and who isn't trying to take your money.

We have a name for such people. They're called scientists. They make a profession of distinguishing what people believe from what is actually true. They aren't perfect, but you can trust them more than, say, Suzanne Somers or Richard Simmons.

A Law of Physics

One thing that scientists generally agree on is that the human body is a machine. For all of its wonderful complexity, it's still basically a device that extracts energy from fuel in order to do work. The work is moving, thinking, reading, yelling at the kids, refinancing your house, and such. And the fuel is, of course, food.

The energy in your food is measured in calories. Your body burns some of them to heat your muscles and organs to their preferred operating temperature. It uses others to power thousands of chemical and mechanical processes that help you play the piano and prune your azaleas.

If any calories are left over, your body stores them as fat. Everyone knows this, but not many people know exactly how much fat. It's one pound for each 3500 calories. In other words, if you eat 3500 calories more than your body needs, you'll gain a pound; and if you eat 3500 calories less than you need, you'll lose a pound.

Now here's what I came to tell you today: The 3500-calorie equation is always true, no matter what diet you're on. It doesn't matter whether you're eating protein or carbohydrates or grapefruit or lobster—the only way to lose a pound is to take in 3500 calories fewer than your body needs. This isn't someone's opinion—it's a law of physics. If it ever stops being true, you won't have a weight problem because the law of gravity won't be true, either. (Also, the Cubs will win the World Series.)

Only Two Kinds of Diet

Download DietPower free trialIf calories are what really counts in weight loss, then why are there so many different diets? Partly because diets with gimmicky names sell books and create jobs for celebrities. And partly because we all wish we could look like Denise Austin or John Basedow without giving up our second helpings of lasagna.

Don't get me wrong. Most of these diets work. But there's nothing magical about why they work. They're always designed to make you—

  • Eat fewer calories, either by limiting your portions or by emphasizing foods that are low in calories but high in bulk. (Appetite-suppressing drugs or supplements also fall into this category.)


  • Burn more calories, by eating foods or taking supplements or drugs that speed your metabolism so your body uses calories faster than you consume them. Many systems that claim to do this actually don't, however. Recent studies of Atkins dieters, for example, showed that their losses stemmed from lower calorie intake. Prescription drugs do speed up your burn rate, but they have side effects that rule them out for all but the morbidly obese.

—or both.

No matter which diet or drug you're on, however, the laws of physics still apply. Eat 500 calories less than your body uses each day and you'll drop a pound a week.

Do Me a Favor

It's easy to count the calories you eat—they're listed on every food's label. But how can you find out the number your body needs? It varies from person to person. It even fluctuates from day to day.

Two ways:

  • Download DietPower free trialGet a breath test.  This measures the amount of oxygen harvested from each inhalation, which indicates how many calories your cells are burning. It requires you to breathe into a plastic bag hooked to an electronic gas analyzer costing tens of thousands of dollars. Instead of buying the equipment, you can do the test at a laboratory for $100 or more—but I doubt you would want to pay that every day. 

  • Use DietPower. DietPower weight-loss software is the only product we know of that measures your calorie needs without expensive equipment. It does so by comparing your weight change every day with the number of calories you've eaten lately. Because it adjusts your calorie budget to the daily fluctuations in your needs, it can guarantee reaching your goal on your target date. To use it, all you need is your own computer and five minutes a day to log your meals. And it's free.

I'm not arguing that you should use DietPower instead of a diet. Although DietPower works beautifully by itself, it can make any diet more effective. Thousands of people have used it with Atkins, Weight Watchers, South Beach, Slim-Fast, Nutri/System, Jenny Craig, and other diets to lose 20, 40, 60, 100 pounds or more and keep it off for years. DietPower works by providing a definitive answer to the universal question, "How many more calories can I eat today and still reach my goal on schedule?" Once you know this, you have total control over your weight.

Now, please do me a favor: When people try to lecture you on the fattening properties of carbohydrate, bleached flour, processed sugar, and such, just tell them, "It's the calories, stupid!"—and send them this article.

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