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Small Change, Big Weight-Loss Payoff

We are a fat nation obsessed with losing weight.

According to a 1999 Centers for Disease Control (CDC) study, 35 percent of America's adults (75 million) are slightly or moderately overweight, and 26 percent (56 million) are obese or grossly overweight. Anyone up to 30 pounds above the target weight for their body size is overweight, says the CDC, and another 30 pounds over target weight is considered obese.

The CDC notes that half of us are trying to lose weight, not only through diet and exercise but by using commercial weight-loss products and services worth $33-$50 billion a year.

There may be a better way: eating 100 less calories a day. We put on 1.8 to 2.0 pounds each year, calculated professor James Hill of the University of Colorado Health Sciences Center in Denver, in an article published in Science (February 7, 2003).

How can we prevent this weight gain? Since each pound is equivalent to 3,500 calories, creating a deficit of about 100 calories daily - the equivalent of 10 potato chips - should allow us to stop gaining at least 1 pound each year, contends Hill.

Eat Less Than You Need

But losing weight is different from not gaining weight, points out Katherine Tallmadge, a registered dietitian and spokesperson for the American Dietetic Association in Washington, D.C. Assuming your body needs 2,000 calories a day to meet its energy requirements - the average for most women - and you consume 300 fewer calories than 2,000 daily, you could shed 30 pounds a year. That's because your body will take the extra 300 calories it needs for energy from stores of fat.

Now, that may sound extreme, but, Tallmadge, like Hill, believes "small changes can make a big difference." Consider this: By halving that 200- to 300-calorie nightly snack, you could drop 15 pounds a year. Step up your level of activity by walking around the office instead of shooting out emails nonstop and you could strip away another 100 calories daily, or 10 pounds a year.

How to Knock Out Calories

Of course, if it were that easy, you wouldn't be reading this now. So how do you hunker down and continuously knock out those 200 to 300 calories a day? The often-repeated formula is to combine eating less calories with regular cardiovascular exercise. Do all three, and you're guaranteed to melt away fat. But be forewarned: Your body can only metabolize a certain amount of fat - 1 to 1.5 pound(s) a week - on a low-calorie diet, says Tallmadge. At some point, the fat will turn to muscle, which is why you want to build muscle when losing weight.