With more than 60 percent of American adults considered overweight and one-third of all American adults considered obese, it’s no wonder many are trying to change their diets and lose weight. In fact, in the United States, we spend about $60 billion a year on weight-loss products and programs. With approximately 75 million people a year trying to shed extra pounds, that’s about $800 per person. But while many of the products sold to dieters can help make a significant difference in shedding those excess pounds, many people may not realize the toll those products could be taking on their teeth.

Dr. Stephen Hill of Allen, Texas, says that despite Americans trying to eat better, cavities are still a big problem.

"I think there’s this misconception that diet foods are healthy foods, but many people don’t realize that these foods have tons of added sugar," he says.

Hill says food manufacturers will often reduce fat in a product only to add sugar to make up for the lost flavor.

"We see it with milk, for example," Hill says. "Fat-free milk often has added sugar to help convince kids to drink it, so you may be lowering your fat content, but you’re not really eating any healthier."

This bait-and-switch of fats and sugars seems to also be common with many "reduced-fat" or "low-fat" desserts, salad dressings and even diet shakes.

"The irony is that you do need fat, but you don’t need sugar," Hill says. "So, you’re essentially removing an ingredient you need and replacing it with an ingredient that you not only don’t need, but that could also be harming you."

Along with increased cavities, excess sugar has also been found to cause diabetes, excess weight and even premature aging. That’s because sugar encourages a natural process in your body called glycation, which speeds up the aging process by forming molecules called advanced glycation (AGE) molecules. The AGE molecules damage the collagen and elastin in your skin. Collagen and elastin are what make skin look smooth and "snap back" when we pull it. As we age, it breaks down naturally, causing wrinkles and sagging - but eating excess sugar, especially after age 35, can speed up the process.

Hill says that both sugar and fat are fine in moderation, but often consumers think they can eat more if the product they're eating is considered "healthy."

"If you’re already consuming twice the sugar in your low-fat salad dressing and then you pour twice as much dressing because it’s lower fat, you’ve essentially poured four times the sugar on your salad than you would have with the full-fat version," Hill says. "That’s an open invitation for the bacteria that causes cavities to have a picnic in your mouth."

Still, Hill says many reduced-fat products can still be better options than their full-fat counterparts, but consumers should do their own due diligence before purchasing them.

"I would encourage any patient looking to lose weight to pay close attention to the labels of the foods they are choosing," Hill says. "Look for reduced-sugar products as well as reduced fat, and compare the full-fat version’s label to the reduced-fat label if you’re not sure what’s different. That, and don’t forget to brush and floss your teeth."