Of all the ingredients in your food, sugar is by far the sneakiest. It's added to all kinds of products you wouldn't expect, such as peanut butter, oatmeal, and bread.

Making matters more complicated, food manufacturers aren't yet required to tell you exactly how much sugar they've added to their products. That means naturally occurring sugars—the kind found in healthy foods like whole fruits, vegetables, and dairy products—aren't separated out from added sugars. Instead, food labels list the combined total grams of both types. Many packaged foods contain both naturally occurring sugars and added sugars.

RELATED: 10 Easy Ways to Slash Sugar from Your Diet

The FDA is working to make added sugars a part of future food labels. For now though, you're not doomed to eat more sugar than you need. (The American Heart Association recommends no more than 100 calories of added sugar a day.)

By comparing sweetened and unsweetened versions in the grocery store aisle, you can start slashing sugar from your diet. Just follow this simple trick:

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