In honor of National Frozen Food Day (it’s today, in case you didn’t know) we’ve asked dietitians to share some pros and cons of frozen foods: products worth stocking your freezer with and pitfalls to avoid. “Frozen foods can be a lifesaver when you don’t have the time or ingredients to make a healthy meal from scratch,” says Angie Murad, R.D., a dietitian with the Mayo Clinic Healthy Living Program. “But not all frozen foods are ones you want to rely on, so you do have to be careful what you choose.”  

What to Look For

The healthiest frozen foods are the single-ingredient ones. “I stock my freezer using the same principles I use when buying fresh food,” says Liz DeJulius, R.D., a dietitian at the Cleveland Clinic Center for Functional Medicine. “I look for high-quality whole foods that I can use as ingredients for making a quick, healthy meal.”

Those would include frozen items such as:

Fruit. Keep bags of berries, mangoes, and other fruit in the freezer to use in smoothies, yogurt parfaits, or muffins. Unlike the fresh variety, you can find them year-round at a reasonable price. Choose products that are free of added sugars.

Vegetables. As with frozen fruit, frozen veggies are a great way to get the produce you love no matter what’s in season. “And since they are picked fresh and flash frozen, the vitamin and mineral content is almost equal to their fresh counterparts,” says Lauri Wright, Ph.D., R.D., assistant professor of nutrition, University of South Florida's College of Public Health. “Another benefit is less waste, since you can take just what you need out of the freezer rather than having fresh produce go bad in the fridge.” Just be careful to avoid packages that contain a lot of added sodium or veggies that come with fatty sauces.

Whole grains and beans. Frozen bags of whole grains (brown rice and quinoa) and beans (black beans and chickpeas) are making it easier than ever to eat more of this healthy food group. “And since these are foods that take a long time to cook, using frozen can be a real time-saver,” says DeJulius. You can find blends of beans and grains or grains and veggies, too, but these might come with seasoning, and sodium. Look for those that have no more than 350 milligrams of sodium per 1-cup serving, and preferably less. Plain frozen beans often have no added sodium compared with canned, which can have 400 milligrams or more per ½-cup serving. 

What to Be Wary Of

The frozen-food aisles can be nutritional minefields if you don’t know what to look out for. While no category of frozen food needs to be totally off-limits, make sure to read labels and know what you’re getting.

Frozen entrées. They’re incredibly convenient when you need a meal that’s ready in minutes, but frozen entrées present several pitfalls. Check the nutrition label to see how much sodium an entrée contains. “Sodium is used as both a flavoring and preservative in frozen foods,” says Murad. “Choose ones that have around 600 milligrams per serving" (and no more than 800 mg). And skip anything that’s fattened up by a heavy cream or cheese sauce. The flip side is that some frozen entrées are so small and low in calories that they may not fill you up enough to count as a meal. “Look for ones that have 350 to 500 calories and at least 3 to 5 grams of fiber to help you stay satisfied longer,” says Murad. If you choose a meal that has fewer calories, round it out with a salad or some fruit and nuts.

Pizza. A double-meat-lover’s pizza with a thick, doughy crust is not the healthiest choice. But a slice or two of thin-crust pizza (ideally made with whole-wheat flour) topped with veggies isn’t a bad option when you’re in a hurry. You can even bump up the nutritional value by tossing a handful of spinach or arugula on top after you cook it. Be wary of the sodium count, however: Pizza is one of the top 10 sources of sodium in the American diet, according to the Centers For Disease Control and Prevention. If the pizza is your entrée, 600 mg of sodium or less is a good number to shoot for, and no more than 800 mg per serving. However, when checking the nutrition information, look at the serving size. It could be the whole pizza (for a personal pie), half the pie, a third of the pie, or one-sixth of the pie. 

Ice cream. This once-in-a-while indulgence will never be mistaken for a health food, but you can make smarter choices when selecting a frozen treat. “Premium ice creams have more fat and therefore more calories,” says Wright. For example, ½ cup of vanilla Häagen-Dazs has 250 calories, 17 grams of fat (10 g saturated), and 20 g sugars compared with the same amount of Breyers Natural Vanilla, with 130 calories, 7 g fat (4 g saturated), and 14 g sugars. “And the more ‘add-ins’—such as nuts, fudge, candy—the more calories, sugar, and fat,” Wright says. Sherbets, ices, and sorbets are lower-calorie options. Whatever you choose, remember to watch your portion size—which is typically about half a cup (not half a pint).

Breakfast sandwiches. These aren’t the healthiest way to start your day. “They’re typically made from eggs, processed meat, and refined-flour bread,” says DeJulius. If you need to make breakfast from the freezer, you’re much better off grabbing some frozen fruit to whip into a smoothie and microwaving a bowl of frozen steel-cut oatmeal (just watch the sugar content).  

Freezer Tips

Just because it’s in the freezer doesn’t mean it’ll keep forever. Ideally, you’ll eat your way through your freezer’s contents within six months. “Package food so that air can’t get in (when it does, ice crystals and freezer burn occur), to help it stay fresh longer,” says Murad. Her tip: Date your packages when you put them in the freezer so it will be easy spot ones that have lingered too long.  

Correction: An earlier version of this article indicated that a ½-cup serving of Breyers Natural Vanilla contains 13 calories. It contains 130 calories.