I'm a 25-year-old extreme couponer who loves to shop at Costco. Here are 13 things I frequently buy.

These protein bars have become my obsession.

Low in carbs, high in fiber, and delicious — they make me think I'm eating dessert.

I eat one pretty much every day, and they end up costing about $0.75 apiece. Similar bars could sell for $2 or more at other stores.

Kirkland's almond butter is a game changer.

A large tub costs under $7, so I've yet to find a better deal. Plus the only ingredient is almonds.

I always have this in my fridge, and I make sure to repurchase it when I'm running low.

I use tons of olive oil and love having the huge jug on hand.

Olive oil can be an expensive staple at many stores, but I save money in the long term by buying it in bulk at Costco for about $12.

I use almond milk every day, so buying it at Costco is convenient and saves me money. Each box of 12 cartons costs just under $12.

I keep just one of these small containers in the refrigerator at a time and store the others in my pantry, so they don't take up precious fridge space.

I go through a lot of coffee, and this product has never disappointed me.

At about $12 a bag, it's great for daily drinking and seems to last forever.

Pro tip: Grind these coffee beans with the industrial grinders by the registers before you leave.

Egg whites are a good, versatile source of protein. For example, you can add them to your oatmeal.

I buy them in bulk for under $9, then usually freeze half of the box when I get home. They keep really well.

I use Greek yogurt almost daily, and I'm getting pretty creative with new ways to incorporate it into my diet, like mixing it with peanut-butter powder.

I also add it to sauces or smoothies and make super-filling, delicious yogurt bowls with fresh fruit and nuts.

Since my job is quite demanding, I've been trying to perfect my go-to five-minute, nutritious meal.

I throw these skewers in the air fryer for a quick lunch, snack, or dinner, and they're great on their own or on top of a salad.

A 28-ounce package costs about $12.

For weekday lunches and dinners, I'll throw a handful of veggies in my air fryer and call it a day.

I usually opt for a green that lasts in the fridge for at least a week — like Brussels sprouts or broccoli — and freeze whatever isn't eaten after seven to 10 days.

Kirkland's organic blueberries are a great price at under $8 a bag. And since they're frozen, I don't have to worry about them going bad.

The frozen cherries are also a favorite of mine — I put them in my chocolate protein shakes.

I love buying chicken at Costco. These huge packs can be intimidating, but you can easily cut them into three separate packages when you get home.

This organic chicken costs roughly half as much as it does at my normal grocery store, so I don't mind buying it in large quantities and freezing it.

I once bought a pack of Kirkland's hard seltzers for a beach trip and they were a huge crowd-pleaser.

They're way more cost-effective than other name-brand seltzers and equally as good — if not better.

Even though you can buy Brownie Brittle at most grocery stores, there's something special about one of these giant, Costco-sized bags.

At under $7 for a 16-ounce bag, this sweet treat is so delicious that I can't resist digging in.

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