Make the Most of Your Metabolism

Is your metabolism really the reason it's often so hard to lose weight?

And, more important, is there anything you can do about it? If you're carrying some extra pounds (and having a hard time losing them), it's tempting to put the blame on a sluggish metabolism.

In fact, experts explored facts and myths about metabolism -- and the good news is, there are things you can do to help boost your body's calorie-burning power.

What Is Metabolism?


Your metabolism, experts say, involves a complex network of hormones and enzymes that not only convert nutritious food into fuel but also affect how efficiently you burn that fuel.

"The process of metabolism establishes the rate at which we burn our calories and, ultimately, how quickly we gain weight or how easily we lose it," says Robert Yanagisawa, MD, director of the Medically Supervised Weight Management Program at Mount Sinai Medical Center in New York.

Of course, not everyone burns calories at the same rate.

Your metabolism is influenced by your age (metabolism naturally slows about 5% per decade after age 40); your sex (men generally burn more calories at rest than women); and proportion of lean body mass (the more muscle you have, the higher your metabolic rate tends to be – a benefit).

And yes, heredity can make a difference.

"Some people just burn calories at a slower rate than others," says Barrie Wolfe-Radbill, RD, a nutritionist specializing in weight loss at New York University Medical Center.

Occasionally, Yanagisawa says, a defect in the thyroid gland can slow metabolism, though this problem is relatively rare.

And here's a fact that may surprise you: the more weight you carry, the faster your metabolism is likely running.

"The simple fact is that the extra weight causes your body to work harder just to sustain itself at rest, so in most instances, the metabolism is always running a bit faster," says Molly Kimball, RD, sports and lifestyle nutritionist at the Oscher's Clinic's Elmwood Fitness Center.

That's one reason it's almost always easiest to lose weight at the start of a diet, and harder later on, Kimball says: "When you are very overweight your metabolism is already running so high that any small cut in calories will result in an immediate loss."

Then, when you lose significant amounts of body fat and muscle, your body needs fewer calories to sustain itself, she says. That helps explain why it's so easy to regain weight after you've worked to lose it, plus the fact that with most weight-loss diets, a big percentage of the loss is from lost muscle. This muscle loss should be avoided at all costs. Well designed nutritious diets will allow you to eat lots, lose fat and maintain muscle. No one can afford to lose muscle.

Though some of the factors affecting metabolic rate can't be changed, happily, there are ways to maximize the metabolism you're born with -- even when you're dieting.

Among the best ways is exercise. This includes aerobic activities to burn more calories in the short term, and resistance training (with weight, hydraulic or air machines or by using the Dynamic Tension principal) so as to build the muscles that will boost your metabolism in the long run.

"Since muscle burns more calories than fat -- even while at rest -- the more muscles you have, the higher your resting metabolic rate, which means the more calories your body will be burning just to sustain you," says Kimball.

Personal fitness trainer Kelli Calabrese MS, CSCS, ACE, notes that every pound of muscle in our bodies burns 35 calories a day, while each pound of fat burns just 2 calories per day.

While 30 minutes of aerobic exercise may burn more calories than 30 minutes of weight training, Calabrese says, "in the hours following the cessation of exercise, the weight training has a longer-lasting effect on boosting metabolism."

Having extra muscle also means you can eat more and gain less.

Adds Yanagisawa: "We don't tell people to exercise while dieting only to burn calories -- we also know that exercise builds muscle and that is what will help you burn more calories and maintain the weight loss you work so hard to achieve."

Some women fear they'll "bulk up" with weight training. But Calabrese, author of Feminine, Fit and Firm, says not to worry.

"Women don't have the hormones necessary to develop those huge muscles, so you can feel good about doing weight training," she says.

Eat More Good Nutritious Foods, Burn Better


Of course, the diet advice we'd all love to hear is "Eat more and lose more weight!" But what really works is "Eat more often, and you'll lose more weight." Small, but frequent, meals help keep your metabolism in high gear, and that means you'll burn more calories overall.

"When you put too many hours between meals, your metabolism actually slows down to compensate," says Kimball.

If you then eat a huge meal -- at the same time your metabolism is functioning as if you're starving -- your body wants to hold on to every calorie.

While this won't make much difference on an occasional basis, Kimball says, make it a way of life and it can get harder to lose or maintain weight.

Kimball's advice is borne out by the findings of a study that was presented at the 2005 annual meeting of the American College of Sports Medicine. Researchers from Georgia State University reported that when athletes ate snacks totaling about 250 calories each, three times a day, they had greater energy output then when they didn't snack.

The study also found that snacking helped the athletes eat less at each of their three regular meals. The final result was a higher metabolic rate, a lower caloric intake, and a reduction in body fat.

Though some of the factors affecting metabolic rate can't be changed, happily, there are ways to maximize the metabolism you're born with -- even when you're dieting.

From supermodels who douse their food with red pepper, to movie stars who swear by green tea, there's no shortage of claims for foods that are said to increase metabolism. But do any of them work?

"Actually, any food will increase your metabolism, mostly in the first hour after you eat -- that's when your system is most revved," says Kimball.

Your best bet for keeping metabolism revved: Build muscles, snack on low-calorie fresh foods, chew your food well and keep moving!