7-Eleven is giving out free 7.11 ounce Slurpees at stores across the United States in celebration of its 84th birthday.

But some are saying that 7-Eleven's refreshing beverages, just perfect for a hot summer day, are a great way to ruin beach bodies across the nation.

According to one article from eHow Health, the Slurpee is the number one most deceptively fattening drink.

There are 220 calories in just 29 ounces of your typical Slurpee. And chalked into that 220 calories are 101 grams of carbohydrates. That's a nearly 1:2 Carb-Calorie ratio. HUGE.

Just to give you an idea of how high that Carb to calorie ratio is, in 12 ounces of Pepsi, there are some 150 Calories with only 42 grams of carbohydrates. That's a nearly 1:3 Carb-Calorie ratio.

And sodas like Pepsi are notoriously fattening.

There are more carbs in 29 ounces of a typical Slurpee from your local 7-Eleven than there are in a whole weat Oroweat muffin, where in 150 calories, there are some 27 grams of carbs.

Consuming an overwhelming number of carbohydrates leads to an increased concentration of fat in the middle, according to a study by the American Journal of Clinical Nutrition, reported by WebMD.

According to a study of 459 middle-aged adults, followed over two years, those who consumed more bread and other carbohydrates increased their waistlines at faster pace than their protein-eating counterparts.

So before you head to 7-Eleven to take advantage of the latest freebie, you better go out and buy yourself a larger swimsuit.