Can You Slim Down and Lose Calories With a Soft Drink?

As proprietors push a calorie-burning beverage, some diet experts are wary.

March 2, 2009, 5:18 PM

March 3, 2009— -- If there is one category of products that could use a healthier image, soft drinks, one could argue, would be it.

The beleaguered, mostly carbonated offerings have suffered various slings and arrows in recent years, ranging from charges they contain too much high fructose corn syrup to studies that back their role in heart disease and other ills.

It's an image that a drink, sold under the brand name Celsius, hopes to shatter. And if the television ad campaign launched this past weekend is to be believed, these drinks go a step beyond zero calories -- they can actually make your body burn calories after you drink them.

Steve Haley, CEO of Celsius Holdings, Inc., said the claims are backed by several clinical studies funded by his company showing that the beverage ramps up the body's metabolism -- allowing those who consume it to stoke their calorie-burning furnaces.

"[Consumers] can replace what they normally enjoy with this," he said. "We're a great replacement for soft drinks, to a point."

The method behind this boost is not magic; rather it's caffeine -- and quite a bit of it. At 200 milligrams of caffeine, a can of Celsius packs nearly twice the amount of caffeine in an eight-ounce cup of coffee.

But Haley pointed out that the calorie-burning power of the drink comes not only from caffeine, but also from other metabolism-boosting ingredients, like the green tea chemical Epigallocatechin gallate (EGCG), chromium and ginger. In addition, he said, the drink contains vitamins, as well as calcium to counteract the bone-robbing effects of caffeine.

In short, Celsius may be the health food industry's answer to the soft drink in something of the same way that a PowerBar stacks up to a Snickers bar.

"It was our intent all along to create a new category," Haley said. "This is a functional beverage -- a net-negative-calorie drink."

Calorie Burn May Work

But could the drink truly knock 100 calories off of your caloric balance sheet, as suggested in the television ads for the stuff?

"Those data are based on averages," said Jeffrey Stout, a professor in the department of health and exercise science at the University of Oklahoma, and lead researcher on the studies that show Celsius' calorie-burning effects. "Some people expend more, some people expend less. But on average, this is what we're seeing."

Diet experts not involved with the product's research agreed that the results are not hocus-pocus.

"The drink does not appear to change basal metabolic rate over time, although it may 'rev' up metabolism briefly," said Dr. David Katz, director of the Prevention Research Center at Yale University School of Medicine. "The primary effect appears to be an increase in heat generation, or thermogenesis. This is plausible."

"The studies cited on their Web site do show Celsius to increase metabolic rate," agreed New York-based weight and nutrition expert Dr. Jana Klauer. "This is no surprise, because the ingredients are stimulants which are known to increase heart rate and blood pressure."

Moreover, Stout noted, the drink appears to stimulate the body's fat-burning mechanisms. So, not just any calories, but fat calories, may be on the chopping block.

But while they agreed that the drink, in principle, would work to burn extra calories, these experts stopped short of glowing reviews when it came to their impressions of the overall health effects of the beverage. Katz, for one, noted that the beverage's claims are still "ahead of the science." And nutritionists had additional concerns.

"There is some evidence that thermogenic beverages have a short-term impact on human metabolism," said Joanne Ikeda, a nutritionist emeritus at the University of California at Berkeley. "However, there is no evidence that anyone has lost weight or maintained their current weight by drinking thermogenic beverages as a component of their diet."

"How long does this thermogenic effect last? Not known," said Keith-Thomas Ayoob, a nutritionist at the Albert Einstein College of Medicine in the Bronx, N.Y., who added that the same effect could be achieved with two cups of coffee and a multivitamin.

"Probably people adapt over time," he said. "Exercise is a better way to jumpstart your metabolism, and it's healthier as well."

Caffeine Concerns

And then there is the matter of all of that caffeine. Haley said that the drink, if consumed responsibly, would not cause people to exceed a safe daily level of caffeine. The problem that Haley, too, acknowledges is that no recommended limit for caffeine has yet been established -- and a certain amount of additional caffeine may have varying effects from person to person.

"The concerns are that the caffeine effects can increase heart rate and blood pressure -- presenting hazards for stroke, increasing insomnia, and other ill effects," said Dr. James Anderson, professor emeritus of medicine and clinical nutrition at the University of Kentucky in Lexington.

"The consumer needs to be aware that they are paying a health price and risk for using these drinks," Anderson said. "Is the health risk of drinking three cans worth a pound of weight loss per week?"

On its Web site, the drink already carries contraindications for those who are sensitive to caffeine, pregnant and nursing women, and children. And Haley noted that the company goes above and beyond when it comes to ensuring that consumers are aware of what they are drinking when they reach for Celsius.

"We put the amount of caffeine on our label," he said. "We don't have to, but a lot of other companies don't want that on there."

Haley added that, as with any product, there is only so much you can do to control what people do with Celsius. He said that last week, he was having lunch with some business contacts, and two of the women he met with ordered the beverage mixed with whisky -- a drink they termed "Celsius and Crown."

"That's not what we're about," he said. "You can choose -- and we have chosen -- not to promote it. We've chosen to go the healthy route."

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