Top 6 Costco Buys to Fuel Your Muscle Growth

A sports dietitian shares the best Costco foods to support muscle growth.

Are you trying to build muscle in 2026? There are certain foods you should be eating, according to Tara Collingwood, MS, RDN, CSSD, LD/N, ACSM-CPT, a Board Certified Sports Dietitian and co-author of the Flat Belly Cookbook for Dummies. The first category? Lean meats and seafood. “Core muscle-building staples for meals,” she says. Also, make sure to eat dairy products, such as yogurt. “Great for snacks and recovery shakes,” she explains. Protein powder can also help you achieve your protein goals. “Handy when you’re on the go or need fast post-workout protein,” she says. And finally, she recommends seeds and fish as “easy add-ons to salads, bowls, and breakfasts for extra amino acids.” You can get most of these at your local Costco. Here are the 6 best Costco foods for muscle building in the new year.

Kirkland Signature Boneless Skinless Chicken Breasts

Kirkland Signature Boneless Skinless Chicken Breasts are one of the best foods to build muscle you can get at Costco. “Lean, high-quality protein is essential for muscle repair and growth, and Costco’s chicken breasts are a versatile staple for meal prepping, everything from stir-fries to burrito bowls,” she says. “Getting enough protein helps prevent muscle loss and supports training recovery and lean chicken delivers it without excess fat.”

Kirkland Signature Greek Nonfat Yogurt

Next on her list? Kirkland Signature Greek Nonfat Yogurt. “A convenient dairy source with roughly 18g of protein per serving, Greek yogurt supports muscle synthesis and makes a great base for smoothies or parfaits. Greek yogurt contains about twice as much protein as regular yogurt, and this one doesn’t have added sugar, which helps keep calories reasonable,” says Collingwood.

Wild Alaska Coho Salmon Filets

Wild Alaska Coho Salmon Filets are another one of Collingwood’s top picks. “Fatty fish like salmon doesn’t just offer high-quality protein (about 39g per serving), but it also provides omega-3 fats, which help with inflammation and recovery. Seafood is a powerful way to add muscle-building nutrients and healthy fats to your diet,” she says.

Whey Protein Powder (various brands)

Costco sells various brands of Whey Protein Powder that are great for muscle building. “When whole food protein isn’t convenient, whey protein powder bridges the gap. A scoop typically delivers around 24g of protein, ideal for post-workout shakes or morning smoothies. Whey offers fast-absorbing amino acids that help kick-start recovery after intense sessions,” Collingwood says.6254a4d1642c605c54bf1cab17d50f1e

Wild Planet Wild Albacore Tuna

Wild Planet Wild Albacore Tuna is another one of Collingwood’s go-to foods for muscle building. “Canned tuna is a high-protein, shelf-stable seafood option that’s extremely versatile for muscle-building meals. A single serving provides roughly 30–33 g of protein, making it a substantial contributor to daily protein targets for strength and recovery. It’s perfect in salads, rice bowls, sandwiches, pastas, or mixed with Greek yogurt for a quick tuna salad,” Collingwood says.

Kirkland Signature Organic Hemp Hearts

Her final pick? Kirkland Signature Organic Hemp Hearts. “While smaller and more concentrated than animal proteins, hemp hearts pack about 10g of protein per 3 tablespoons, plus healthy fats and minerals. Hemp seeds are a great plant-based add-in to smoothies, oatmeal, or yogurt to bump up your protein intake,” says Collingwood.

Leah Groth