Here are six different ways that manufacturers oversell the health benefits.

Stroll down the aisles of any supermarket, and you’ll see plenty of food labels claiming that the product fights heart disease, improves digestion or even helps prevent cancer. But are these claims true? The FDA has been cracking down on health claims that appear on food labels. For example, the agency recently told the manufacturer of the snack Chiquita Pineapple Bites with Coconut that it was misleading to claim that the product has antioxidants and phytonutrients. According to the FDA, the product is also not low in calories as implied on the label and does not contain real coconut.

At the same time, there are a number of perfectly legal — but misleading — ways that manufacturers can overstate their products’ health benefits. How to avoid six of the most commonly used food-labeling tricks…

Trick 1: Serving sizes may “hide” calories. The Nutritional Labeling and Education Act requires packaged foods to carry a “Nutrition Facts” panel summarizing the foods’ calories… fat, carbohydrate and sodium content… and other important nutritional information.

Here’s where the sleight of hand comes in — calories and other nutritional information are always given on a “per serving” basis. When consumers consider how a particular food will affect their health, they should always note its serving size and the total number of servings per container — both are listed at the top of the Nutrition Facts panel. However, many consumers fail to recognize how much of the food (or the number of servings) they actually consume.

That’s due, in part, to the fact that current serving sizes as set by the FDA are based on surveys conducted more than 20 years ago. Research shows that average portion sizes have grown significantly since then.

For example, the nutrition-label serving size for ice cream is one-half cup and for pasta is two ounces dry weight — amounts that are, in reality, much less than most people typically eat nowadays at a sitting.

Individually packaged items can be even more deceiving. For example, I recently found pound cake that was 300 calories per serving. Not so bad — until you realize that each individually wrapped slice contained 2.5 servings packing 750 calories!

Trick 2: “Zero” fat doesn’t necessarily mean no fat. According to the FDA, if a product contains less than 0.5 g per serving of any type of fat, including trans fat (the most dangerous form of fat, since it boosts dangerous LDL cholesterol and also lowers protective HDL cholesterol), the amount can be rounded down to 0 g in the Nutrition Facts panel. To see whether “zero” trans fat on a label really means zero, go to the ingredient list. If you spot any “hydrogenated” or “partially hydrogenated” fats or oils, you could be consuming as much as 0.49 g of trans fat per serving — and that can really add up if you eat multiple servings.

Trick 3: “Natural” foods can contain unhealthful ingredients. Calling a food “All Natural” or “100% Natural” often boosts sales — but it says nothing about how many calories or how much fat, sugar and/or sodium the food contains. Because the term “natural” is loosely defined, it can appear on foods that aren’t healthful. Foods or beverages containing such added ingredients as high-fructose corn syrup may claim to be “all natural.”

Trick 4: “Reduced” and “light” are relative terms. To be labeled as having “reduced” calories, fat, cholesterol, sodium or sugar, a product must simply have 25% less of that substance than representative “normal” versions of that food.

To be labeled “light,” a product must have either 50% less fat or one-third fewer total calories than normal. But labeling a product “reduced” or “light” still doesn’t mean that it is necessarily low in overall fat or calories.

So, even though a product labeled “light in sodium” has had its sodium reduced at least 50% below normal, its sodium content is not necessarily low. For example, “light” soy sauce contains 500 mg to about 900 mg of sodium — approximately 20% to nearly 40% of the recommended daily intake for the general population — per tablespoon.

Bottom line: Before buying any “reduced” or “light” product, be especially careful to check calories, fat and sodium content.

Trick 5: “Fat free,” “low fat” and “no added sugar” don’t necessarily mean low in calories or sugar. Manufacturers are well aware of the “halo effect” — that is, a food that claims one health benefit gives the impression that it is healthful in all ways. However, foods can have low fat content yet still be high in sugar and total calories. Similarly, foods labeled “no added sugar” could have lots of natural sugars, which have just as many calories as refined sugar. Always check sugar content and calories before buying.

Trick 6: “Made with” claims have lots of wiggle room. Another potentially misleading package statement is the “made with” claim. For example, a product labeled “organic” must have at least 95% organically derived ingredients — but one labeled “made with organic ingredients” needs to contain only 70% organically derived ingredients.

More problematic are the phrases “made with whole grain” or “made with whole wheat” — which can be used even if a product contains primarily ordinary white flour and only a small amount of whole grain. If you see this term, check the ingredient list to see how high “whole-grain flour” appears on the list and whether “unbleached” or “enriched” flour is ahead of it. Food manufacturers are required to list all food ingredients in descending order of weight.

Even better: Look for products with a whole grain as the first ingredient or a “100% whole grain” stamp from the Whole Grains Council, a nonprofit advocacy group that helps consumers find high-quality whole-grain food products.

Similarly, a food labeled “made with real fruit” only has to contain small amounts of a single fruit, which could come from concentrate, and can have unlimited amounts of added sugar and artificial flavorings. For example, a fruit snack called Betty Crocker Strawberry Splash Fruit Gushers claims to be “made with real fruit” but contains only pears and strawberries from concentrate, plus 12 g of sugar per 25 g serving and Red No. 40 dye to provide the “strawberry” color.