A dietitian’s guide to shopping at Costco

Whether you’re heading into Costco for the first time or the 50th time, the abundance of options can be overwhelming. There are TVs! Hand soap! Packs of 50 croissants! It can be tempting to just stress-buy a couple tubs of chocolate covered almonds and call it a day.

But you’d be missing out: A swing through Costco can stock your fridge, freezer, and pantry with lots of nutritious items. “Costco can be a great place to shop for people focused on healthy, whole foods, especially when convenience, budget, and consistency are a top priority,” says Jordan Langhough, R.D., a registered dietitian and certified personal trainer in Charlotte, North Carolina. 

But first, you need to come to terms with the large package sizes. Yes they may be more expensive up-front, but they can save you money in the long-run. “Buying whole foods in bulk, especially shelf-stable options, can help lower the cost per serving,” says Langhough. Next, you need to know what to look for so you can stock up now and use your haul in nutritious meals for weeks to come. To help, we talked to registered dietitians for their best advice on the best healthy foods at Costco — as well as what mistakes to avoid.

While each Costco store can have different items, there are some staples that you can count on being available. Here are six options registered dietitians always look for:

• Oats: A 10-pound container of old fashioned oats can be found for less than $10 and will make more than 110 servings. Oats have a type of soluble fiber called beta glucan, which has been shown to help control appetite, reduce cholesterol, improve gut health, and support healthy immune system functioning. 

• Greek yogurt: “Costco has large tubs of full-fat and nonfat plain Greek yogurt, as well as single-serve flavored options,” says Lainey Younkin, M.S., R.D., a registered dietitian based in Boston. Thicker, strained-style yogurts have more protein than traditional yogurt, which is why Greek is her go-to. For example, one cup of nonfat Greek yogurt is about 133 calories and delivers 23 grams of protein.

• Single-serve hummus: A large tub of hummus can seem like a good idea, until you realize you can’t possibly eat that much before it goes bad. Unless you go through a ton of hummus, dolloping it on salads, grain bowls, and using it as a dip for veggies, follow Langhough’s lead and get the single-serve hummus cups. They last a lot longer, since you leave them sealed until you’re ready to eat them. “I like to buy these for easy grab-and-go options,” says Langhough. “They are great to add to a lunch or pack as a snack with some crackers.” 

• Rotisserie chicken: This item actually has a cult following. “I know people go crazy over Costco rotisserie chicken,” says Cassandra Lepore, M.S., R.D., a registered dietitian based in the New York City area. It’s a great choice to have on hand because rotisserie chicken is high in protein. (A 3.5-ounce serving of skinless rotisserie chicken breast has 135 calories and 27 grams of protein.) This chicken is also on Younkin’s list: “Having rotisserie chicken on hand weekly takes the pressure off cooking.” She recommends adding chicken pieces to soups, salads, and wraps for lunch and dinner. 

• Hard-boiled eggs: Having pre-boiled (and pre-peeled!) eggs on-hand make it easy to grab a high-protein snack (each egg has six grams). Costco carries boxes of 32 hard-boiled eggs, which comes in 16 two-egg packs. 

• Canned beans: People who eat about two servings of beans per day have a lower BMI, body weight, and waist circumference compared to those who don’t eat any, research suggests. Eight-pack cans of black beans and chickpeas can be stored in your pantry for a long time, ready to be used for chilis, soups, and salads, says Younkin.

Depending on your freezer space, these are great items to stock up on:

• Frozen vegetables: About 90 percent of people don’t eat enough vegetables. If you’re trying to eat more, frozen veggies are a great option since they’re prepped already. “Buy frozen vegetables that you know you like and add them to meals,” says Lepore. Some great options include vegetable medleys (like peppers, onions, and mushrooms), riced cauliflower, green beans, and “ sheet pan vegetables.” You can even purchase a large container of fresh baby spinach to freeze — and then easily grab a handful whenever you need some for a smoothie or omelet. 

• Frozen fruit: One way to bring down the cost of fruit is to buy frozen. “In large quantities, you’re typically getting the most bang for your buck,” says Lepore. Frozen fruit can be microwaved for a syrup-like sauce, tossed in a blender for a smoothie, or made into a healthier fruit crisp for dessert. Some frozen fruits, like cherries, also are great to snack on straight out of the freezer.

• Cooked proteins: Sirloin steak, chicken sausage, meatballs, chicken strips, egg bites — there’s a huge range of already-cooked proteins to choose from at Costco. “These are especially helpful for busy weeknights when I need dinner to be quick and easy,” says Courtney Kassis, MS, R.D., a registered dietitian in the Philadelphia area.

• Raw chicken breasts: If you have freezer space, the 6-pound package of Kirkland Signature Fresh Boneless Skinless Chicken Breasts is a great add to your cart. “The packages often come with two chicken breasts per package, and six packages come with it, so you’re getting 12 total chicken breasts,” Langhough says. They are in individual packages, so you can freeze them and take them out as needed. 

• Nuts and seeds: Adding nuts and seeds to your regular diet comes with a ton of health benefits. Research suggests that having a handful of these foods daily may help reduce your risk for heart disease, as well as improve longevity. But they can be expensive when you buy them at your local grocer. Not so at Costco. For example, a 2-pound bag of hemp hearts is $15 and can last you for months. While these don’t come frozen, nuts and seeds can go rancid due to their unsaturated fatty acids, so store the bags in the freezer and grab some when you need them — no thawing required.

• Convenience foods: It’s not just whole foods you should look for, Costco has also a lot of prepared items that make healthy eating super convenient. Frozen cauliflower pizza can be dressed up with additional veggies and your protein of choice, says Kassis. Veggie-based frozen muffins and frittatas are other convenience finds that you can throw into the microwave and pair with some fruit. “These are great to keep in your freezer for busy mornings,” Kassis says.

Costco is full of good deals, but only if you end up eating what you bring home. And things can go sideways quickly. For example, you buy multiple loaves of bread only to have one go bad before you can get to it. Or think you’re suddenly going to start eating loads of blueberries and mangoes and then…don’t. Be realistic when buying fresh foods and store things properly when you get home. Kassis recommends freezing half of your bread right away, and if a fruit is a good deal, you can wash, peel, and cut it up, then freeze it. 

On the topic of storage, take any large bags of snacks and repackage them so they don’t go stale. “We have made the mistake of buying the mega-sized bags of popcorn, pretzels, and cereals,” says Langhough. “The problem is that these bags don’t reseal, so you’re often left with stale food after a few days of opening.” This can be helped by transferring the food into a few smaller airtight containers. 

And finally, know that you like something and have tasted it prior to buying a large volume. “I have bought protein bars in a 24-pack that I never tried before,” says Kassis. “I learned late that I didn’t like them.”

Costco is a great place to get good deals on nutritious foods. Registered dietitians recommend focusing on buying precooked and fresh lean meats, frozen vegetables and fruits, larger quantities of nuts and seeds, and, of course, their famous rotisserie chicken. Make sure you’re realistic about what foods you like to eat so that you don’t buy a lot of something that you may not like or get through. And when you get home, store your foods in resealable containers or the freezer to help them last longer.