It can be easy to forget that food is a business. Although some honest companies have your health and wellbeing as a top priority, a large number of companies exist whose one and only goal is to sell you a product. That means they’ll do anything possible to catch your eye and convince you that buying their product is a smart decision.

Food makers often take advantage of labels such as “reduced-fat” or “low-sodium” to trick consumers into believing a product is a healthy choice. But what do these claims really mean? How much fat is reduced? And what other ingredients are taking the place of reduced or eliminated ingredients? STACK took a look at the truth behind these claims to help you see what lies behind the marketing.

Sugar-Free

What it Means: For a product to be labeled sugar-free, it must have under .5 grams of sugar per serving.

Sugar-free products sound awesome—all the sweet taste you love, but without the risk of obesity, tooth decay, diabetes and heart disease that come with sugar. But that’s not exactly how it works. Sugar-free products usually take advantage of artificial sweeteners, which, while not technically sugar, might actually be worse. For one, they’re downright unnatural. Artificial sweeteners are a modern construct, meaning our ancestors never ate them. And just like sugar, artificial sweeteners can be addictive. One study conducted with rats found that they were more easily addicted to saccharin, “an intense calorie-free sweetener,” than to cocaine.

A different study found that consuming artificial sweeteners instead of sugar actually causes greater weight gain than regular sugar. Sugar has a way of signaling to our bodies the amount of calories we’re intaking, which means it can help us feel satiated and combat overeating. This same property is not found in articial sweeteners. One study claims, “consuming noncaloric sweeteners may promote excessive intake and bodyweight gain by weakening a predictive relationship between sweet taste and the caloric consequences of eating.”

At the end of the day, many sugar-free products’ nutritional facts aren’t even much better. For example, compare the normal Tastykake Cream Filled Chocolate Cupcakes to the “sugar-free” variety. Gram for gram, the normal variety only has 28 more calories, but the sugar-free variety is higher in fat (14% of your DV compared to 9%), saturated fat (15% compared to 8%), cholesterol (7% compared to 1%) and sodium (9% to 7%). If sugar-free sweets seem too good to be true, that’s because they are.

Fat-Free, Low-Fat, Reduced-Fat

What it Means: For a product to be labeled fat-free, it must have less than .5 grams of fat per serving. To be labeled low-fat, it must have three grams or less of fat per serving. To be labeled reduced-fat, it must have at least 25% less fat than comparable products.

The appeal of products low in fat or free of fat is easy to understand. On the most basic level, hearing that a food is fat-free may cause you  subconsciously to conclude that it won’t make you obese—a.k.a., “fat.” But this simply isn’t true. Many of these products have nearly the same amount of calories as their “full fat” counterpart, and some are higher in sugar, sodium or other troublesome ingredients. This can be especially problematic since people tend to overeat foods labeled low-fat, believing these foods are lower in calories as well. A Cornell University study found that people ate up to 50 percent more when a package was labeled “low-fat” compared to a package with no such labeling.

Say you’ve bought Breyer’s Fat-Free Strawberry Ice Cream instead of their standard Strawberry Ice Cream. The fat-free version has only 20 fewer calories and a gram less sugar per serving than the standard version, but its ingredient list is four times longer. Those facts alone make it a questionable option, and if you end up overeating (as one tends to do when consuming low-fat or fat-free products), you’re really digging yourself a hole. And it isn’t just sweets with these labels that you should look out for. Cheez-it Reduced-Fat crackers, for example, have 3.4 fewer grams of fat per serving than original Cheez-its, but only 22 fewer calories. Yet they’re actually higher in carbohydrates and sodium than the original.

Low-Sodium

What it Means: For a product to be labeled low-sodium, it must contain less than 140 mg per serving.

Many of the same issues that exist with products marketed as “low-fat” exist with products labeled “low sodium.” In the case of salty snacks, such as corn chips, a person is apt to believe that the “low-sodium” version is healthier than it actually is, since the main nutritional complaint about corn chips is that they’re too salty to be healthy.

Much like low-fat items, just because a product has a reduced amount of one ingredient does not mean other troublesome ingredients were reduced as well. Take for example, Tostitos Rounds Torilla Chips. Although the “low-sodium” version is lower in sodium than the standard (albeit only by 60 mg per serving), it still contains the same amount of calories, fat and saturated fat. When those numbers are all fairly high, that’s an issue.

Light, Lite

What it Means: For a product to be labeled as light, it must contain a third fewer calories or 50 percent less fat than comparable regular products.

Light products seem like a no-brainer. They’re usually lower in both calories and fat, and the word “light” (or “lite) alone makes you feel like you’re making a healthier choice. But issues can arise when other ingredients are increased to make “light” products more palatable.

For example, Hidden Valley Light Buttermilk Ranch dressing is much lower in both calories and fat than the non-light version. But if you let your eyes wander to the lower half of the nutrition label, you’ll see that the light version is actually significantly higher in sodium than the non-light version. But when people see that the light version is lower in calories and fat, they might feel free to toss that dressing on everything and anything. When it’s high in sodium and a standard serving size is rather small, that can become an issue.

Made With Whole Grain, Made With Real Fruit

What it Means: Products must include some whole grains or real fruit to make this claim, but not in any specific amount.

Alright! I’m eating something made from real fruit or whole grain! The box told me so! The problem with this thinking is that the product can contain a very small amount of these ingredients and still get away with plastering misleading claims on their packaging. The legality of some of these labels is in under review, as the FDA is slowly making changes to curb this type of false advertising. But since such changes can take an excruciatingly long time, you deserve to know what to watch out for.

The Center for Science in the Public Interest released a statement in 2012 regarding rampant “misleading whole grain claims” on store shelves. “Some food manufacturers making whole grain claims or using words like ‘multigrain’ on labels are just trying to obscure the fact that the products are mostly made with highly refined white flour,” the release stated. The statement ended by urging the FDA to mandate producers to include the total amount of whole grains (in grams) and the percentage of grains that are whole with vague labels such as “made with whole grain.”

The “made with real fruit” label is guilty of many of the same offenses. Several companies have been hit with lawsuits for misrepresenting the amount of real fruit in their products, but few legal changes have been issued by the courts.

For instance, Pop-Tarts came under attack a few years back for a prominent “real fruit” label on its packaging. Yet today, their website still shows packaging that displays “Baked with Real Fruit!” front and center. A simple look at the ingredients list reveals how little real fruit is in a Pop-Tart. Instead, it’s mostly sugar and high fructose corn syrup. Instead of buying junk food with ambiguous “real fruit” labels when it actually contains almost no real fruit, opt for eating some actual fruit. Crazy idea, right?

With respect to whole grains, the ingredient list is your best friend. Since ingredients must be listed in descending order of volume, a true whole grain product will have certain ingredients listed first. Check out this handy table to see exactly what ingredients you should be looking for.