Updated

During the past three decades, obesity in America has been on the rise, in part due to increased calorie consumption and portion sizes. Did you know about half of this increase can be attributed to sweetened beverages? A recent study in the American Journal of Clinical Nutritionshowed that around 37 percent of our total daily liquid calories come from sugar-sweetened drinks. Not only has the number and variety of calorically dense drinks been on the rise, but the average soft drink portion is now 20 ounces, a whopping 50 percent greater than the 12-ounce portion of thirty years ago!

So what exactly does this mean for our waistlines? One 20-ounce soda has about 250 calories and 68 grams of sugar - with no nutritional benefits. That's like eating 17 teaspoons of sugar, much more than you would add on your own to your morning coffee or tea. Adding an extra 250 calories every day will lead to gaining 25 pounds in just one year!

In addition, studies suggest that when people consume more calories in the form of beverages, they do not compensate by eating or drinking less. This is because the calories are often "empty," or nutrient-poor, and do not get your metabolism moving the same way a nutritious meal or snack would. Especially with these jumbo portions, it is easier to drink more than eat a greater amount of solid food, which would offer more satiation than the liquid calories.

With the increasing obesity rates, even the government is taking action on this matter. According to the Wall Street Journal, Senate leaders are considering new federal taxes on soda and other sugary drinks to help pay for an overhaul of the nation's health care system. Its unclear how much the tax will be, but even at a proposed 3 cents per can, about $24 billion would be generated over the next four years. What would the government do with the money? Expand health insurance coverage to all Americans. Whether or not this would help decrease soda consumption is unclear, but it might make Americans think twice about what they are drinking.

The bottom line is if you're just starting out on a weight loss plan, the easiest way to cut calories is to eliminate liquid calories from soda, juice, and sweetened teas. Stick to water, unsweetened teas/coffee and other zero-calorie beverages. Every pound is equal to 3500 calories so if you cut out that 250-calorie drink every day, you'd lose at least 2 pounds every month. And that's without any other change in your diet!

Tanya Zuckerbrot, MS, RD is a nutritionist and founder of

. She is also the creator of The F-Factor DietaC/, an innovative nutritional program she has used for more than ten years to provide hundreds of her clients with all the tools they need to achieve easy weight loss and maintenance, improved health and well-being. For more information log onto

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