I'm a personal trainer. Here's how I spend about $100 a week at Costco to feed my family of 6.

Potatoes are a family favorite and we eat them mashed, roasted, or baked or put them in soups or curries. They're a filling, nutrient-dense carbohydrate that keeps my family full and energized.

The 15-pound bag of potatoes lasts us about a month and costs $6.49, or about $1.62 per week.

Sealtest cottage cheese, my top choice for protein, is high in calcium and more affordable than the Greek yogurt that I've seen. I combine cottage cheese with herbs and roasted garlic to make dips to eat with pita and vegetables.

I also use Sealtest cottage cheese as a base for breakfast with boiled eggs, cucumber, and tomatoes or in my favorite ground-chicken lasagna recipe.

A two-pack of 500-gram containers costs $6.19 and lasts us one week.

We also like to buy Christopher-brand carrots, another affordable, nutritious vegetable. I like to cut them into matchsticks to eat with homemade ranch, hummus, or cottage-cheese dip.

They're also fantastic in bibimbap or sushi bowls, stir-fry, or stews, and shredded on top of salads. I plan to make carrot soup this week and freeze some for later.

A 10-pound bag is $7 and will last us about a month for $1.75 per week.

For me, Fancy Lebanese Bakery's whole-wheat pita bread is a fantastic, versatile buy. We eat it with homemade Greek- or Middle-Eastern-style meatballs and hummus or have it with tzatziki, lettuce, tomato, and cucumber.

I pack the pita bread with dips, carrots, and other veggies for school snacks. My kids also have pita bread with tomato sauce and cheese as a mini-pizza-style snack or lunch.

We freeze extra bread and thaw it as needed and even use stale or leftover pita to make chips. Five packages of whole-wheat pita cost $3.69 and last us two weeks for $1.85 per week.

Garlic is a cooking essential because just a little bit delivers so much flavor. Recently, I've noticed a significant price increase for garlic at my local grocery store so I've been buying it in bulk at Costco.

I preserve some of the garlic so I can use it before it sprouts. I roast it to save for flavoring soups, mashed potatoes, homemade salad dressing, toast, and pasta sauce. I also mince and freeze garlic or preserve it in oil.

A 3-pound bag of garlic retails for $7 and lasts us about three weeks, costing about $2.33 per week.

Dunya Harvest chickpeas and other beans are cheap, filling proteins and carb sources that can be used in a lot of meals and snacks.

This week, I'm making chickpea soup with some leftover cooked ham, kale, roasted garlic, and diced tomatoes. I also use chickpeas to make hummus and a dessert dip with canned pumpkin, maple syrup, and chocolate chips for my children's lunches.

I sometimes cook them and freeze them, which saves more money (8 pounds for $10), but a box of 12 costs $17. A pack of 12 lasts us about two weeks for $8.48 per week.

I roast Kirkland Signature chickens, each with different seasonings, to use for a couple of weeks. I also use the bones, along with vegetable scraps, carrots, and herbs, to make a broth.

Three whole chickens cost about $30 and last us two weeks at $15 per week.

Kirkland Signature rice is a filling pantry staple and I think Costco has the best deals on the good-quality stuff. We buy large bags to use as a base for stir fry, curries, and rice bowls or to make a side dish when seasoned for Mexican and Middle Eastern-inspired meals.

One 8-kilogram bag of rice lasts us about three months and costs $20 at about $1.70 per week.

Cheese can be an expensive grocery item, but it adds so much flavor and substance to meals so we never go without it.

We use Kirkland Signature cheese as a topping, a filler in sandwiches, and a snack for my kid's lunches and put it in homemade pizza, tacos, and eggs. This week, we're using it to make homemade macaroni and cheese with ham.

A 2 1/2-pound block of cheddar cheese is $15 and lasts us two weeks for about $7.50 per week.

We eat a lot of Burnbrae Farms eggs since they're a tasty and filling whole-protein source.

Most of my family has them for breakfast, and we also use them in shakshuka (a Turkish dish made with tomatoes and eggs), chilaquiles, and egg salad. Typically, we go through a pack of 30 eggs or even more each week.

A 30-pack of large eggs is $9.39 and lasts us one week.

Kirkland Signature natural peanut butter is a staple. We use it in savory and sweet recipes, sauces, snacks with toast and yogurt, or homemade fruit dip. Though it's a pricier item, we find that two jars last at least six weeks.

A two-pack costs $13.39, which works out to be about $2.23 per week for us.

Clementines, a family favorite, make a quick and easy snack for lunchboxes or any time so we keep them stocked. They're a sweet, vitamin C-rich treat to eat by themselves or to add to salads, yogurt, and smoothies.

A large bag from Costco is $6.49 and lasts us two weeks for about $3.25 per week.

Bananas are a delicious starchy carb before or after workouts. We put them in yogurt, oatmeal, and smoothies, and on toast with peanut butter. I save any brown ones for mug cakes and baked goods or freeze them for smoothies.

We buy two bunches of bananas per week at $2 each for about $4 per week.

Nature's Touch frozen broccoli is a cost-effective way to get some green vegetables without risking spoilage.

Most nights, we have broccoli, green beans, or another green vegetable as a side dish. This week, we restocked broccoli to use in stir fry and or soup.

A bag lasts us about a week and costs $10.

We use the Attitude Fraiche mixed greens for sandwiches, quick side salads, and a garnish on rice bowls.

I think mixed greens are tastier and more convenient than lettuce since I can just toss it in a bowl with a bit of olive oil and lemon juice and add any vegetables I have for a quick salad.

One container lasts us a week and costs $3.79.

Crunchmaster multigrain crackers are a convenient snack, whether packed in the lunchbox, consumed after a workout, or as an after-school snack. We eat them with cheese, pickles, dips, or by themselves since they're tasty as is.

A box costs $10.50 for about $5.25 per week for my family.

We eat Olivia-brand shrimp once or twice a week to create variety in our protein choices.

Shrimp is a family favorite, and we use it for tacos, rice bowls, and pasta. We usually cook a big batch and eat leftovers for lunch.

One bag costs $30 and lasts us two weeks for about $15 per week.

I think the variety packs of Antonio Amato pasta at Costco are excellent value. We use them for meals like spaghetti bolognese, homemade mac and cheese, and shrimp in spicy tomato sauce.

We get a 10-pound bag of pasta for $11 that lasts us a month or more for about $2.75 per week.

Total weekly spending: $102.08

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