With salad dressings, you'll need to consider several things. First, check out the calorie count as well as the number of fat grams. Reduced-fat and fat-free dressings may not be low in calories since sugar is often added to replace the fat. Also pay attention to the type of fat—saturated, monounsaturated, or polyunsaturated—in the product. Taking low-fat a step further, Benecol and Take Control dressings contain sterol esters, plant-derived substances that have been shown to reduce "bad" cholesterol. If possible, opt for a dressing with less than 4 g of fat and less than 75 calories per serving.

Not all peanut butters are created equal. The healthiest choices are those that contain only peanuts and salt. Some have trace amounts of hydrogenated vegetable oils (trans fatty acids that threaten heart health) or corn syrup. If you're watching your total fat intake, opt for reduced-fat varieties with 11 or 12g of fat, as opposed to their full-fat counterparts with 15 or 16g.

Don't assume that breads with names like "whole grain" are good sources of fiber. A real whole grain bread will list "whole grain wheat flour" as the first or second ingredient. Also, look for brands that contain at least 3 g of fiber per serving.

Canned soups are notorious for being high in sodium and fat. And beware that just because soups claim to be low in fat doesn't mean that they're also low in sodium. Look for soups with less than 500 mg of sodium and less than 3 grams of fat per serving.

Spaghetti sauces, like canned soups, differ in sodium content and fat content. Look for a sauce with fewer than 500 mg of sodium and 3 grams of fat per serving. Alternatively, you can use unseasoned canned tomato sauce, adding your own minced garlic and fresh basil. The benefit: You can find brands with as little as 0 grams of fat and 200 mg of sodium.

Avoid juice products that don't say "100 percent juice," and seek out those that have been fortified with Vitamin C and calcium.