Shopping for picnic food for your Memorial Day bash? The burgers, hot dogs, and other items on your grocery list may be higher in calories than you realize. But that's not the case with all picnic foods, and some may have hidden health benefits.

“We normally don’t think of picnic foods as being good for you, but many of them are,” says Maxine Siegel, R.D., who heads Consumer Reports’ food lab. “For example, watermelon is low in calories and a source of potassium and the heart-healthy antioxidant lycopene. Corn on the cob is a good source of magnesium and potassium and supplies vitamin A in the form of lutein and zeaxanthin, which are antioxidants important for eye health.”

And you can throw any vegetable on the grill—asparagus, corn, mushrooms, peppers, even romaine lettuce. For dessert, try grilling fruit such as peaches, pineapple, plums, or watermelon. “The sugars in the fruit caramelize, bringing out their sweeteness even more and adding a depth of flavor,” says Siegel.

Another picnic foods tip: consider substituting leaner meats to cook on the grill, such as chicken and fish, for beef burgers and hotdogs.

Whatever’s on the menu at your celebration, remember to eat reasonable portions. To help, we’ve calculated what 100 calories of 12 common cookout and picnic foods looks like.