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Top 5 Protein Bars at Costco?

I've always been interested in objectively evaluating protein bars, and a recent article in 'Eat This' propelled me to investigate this and provide my analysis. This website had dieticians rate the top 5 protein bars. Before I begin, I suggest protein bars shouldn't necessarily be a replacement meal but rather a snack someone may grab if they're hungry and need a little energy. Protein bars should only be a basic supplement to one's diet, it may help keep snackers a little further away than a candy bar or a bag of chips. From a health perspective, when you make small improvements in your diet, they may eventually become major improvements.

These are the top five protein bars recommended by the 'Eat This, Not That' website. This website evaluation is compiled by several of their dieticians regarding their recommendations of the best bars. A few things I’ve gathered from the article. A protein bar should be around 200 calories, a reasonable amount based on a 2,000-calorie diet. It’s important to pay close attention to saturated fats as going over 6 grams, that’s to keep an eye on. And of course, they recommend some fiber to help you feel fuller for longer. To close, they gave no specific dietary criteria on this published site regarding rating the top 5 bars at Costco. Which means I have to wonder and critique their reasoning behind the very best protein bars. So, here are the top 5 protein bars that can be purchased at Costco and written by Toby Amidor for the website: 'Eat This, Not That.'

Number One:

RX BARS. PER 1 CHOCOLATE SEA SALT BAR: 210 calories, 9 g fat (2 g saturated fat), 260 mg sodium, 23 g carbs (5 g fiber, 13 g sugar), 12 g protein 1.83 ounces (52 grams per bar). Total box of 520 grams, $18.99 (online).

Number Two:

SIMPLY PROTEIN. PER 1 PEANUT BUTTER CHOCOLATE BAR: 150 calories, 4.5 g fat (1 g saturated fat), 280 mg sodium, 14 g carbs (7 g fiber, 1 g sugar), 15 g protein, 1.41 ounces (40 grams per bar). The total box is 600 grams, which is $24.99 (online).

Number Three:

KIRKLAND SIGNATURE. PER 1 BAR: 190 calories, 7 g fat (2.5 g saturated fat), 190 mg sodium, 22 g carbs (10 g fiber, 2 g sugar), 21 g protein, 2.12 ounces (60 grams per bar). Total box of 1200 grams, $23.99 (online).

Number Four:

READY CHOCOLATE BAR. PER 1 BAR: 200 calories, 7 g fat (1.5 g saturated fat), 160 mg sodium, 23 g carbs (7 g fiber, 10 g sugar), 15 g protein. 1.83 OUNCES (53.6 grams). The total box is 1300 grams, online at $33.99.

Number Five:

PURE PROTEIN BARS. PER 1 bar. 200 calories, 7 g fat (3 g saturated fat), 200 mg sodium, 17 g carbs (1 g fiber, 2 g sugar), 20 g protein. 1.76 ounces (50 Grams). The total box is 600 grams, online at $16.09 on Amazon.

My Conclusions To Top 5 Protein Bars at Costco Article

Number One.

Using this comparison, you are essentially comparing apples to oranges. For example, the top two rated bars are the RX Bars and Simply Protein, and each bar is 52 and 40 grams, respectively. However, the Kirkland signature bars contain 60 grams, so comparing them with the fluctuating sizes makes it hard to make a fair comparison.

(Please see my second chart below for the exact volume vs volume comparison.)

Number Two.

The online article chooses the RX Bars as the best protein bars to buy at Costco (1.83 ounces per bar); it has 260 mg sodium, 9 grams of fat, 23 grams of carbs, 13 grams of sugar, and 12 grams of protein.

Comparing this to the Kirkland Signature bars (2.12 ounces per bar) it has 190 mg of sodium, 7 grams of fat, 22 grams of carbs, 2 grams of sugar, and 21 grams of protein.

How can these dieticians rank the RX Bars higher than the Kirkland bars? How can this be considered the best protein bar with only 12 grams of protein? Even though this website rated it first, it finishes last regarding the protein provided. How can this protein bar be rated first for healthiness when it has 13 grams of sugar? In addition, the individual Kirkland bars provide 20 percent more volume per bar with fewer calories, less fat, less sugar, and much less sodium per actual bar. At first glance, or any glance for that matter, the Kirkland bars should achieve a higher ranking than the RX Bars. 


Number Three.

From a volume perspective, let’s compare the Simply Protein bars (ranked second) against Kirkland. Because SP is 50% less in volume, I multiplied their actual amount by 50% to reach a more adequate comparison between SP and Kirkland. After the volume increase, these two are very comparable regarding Carbs (10.5 vs. 10), Fiber (10.5 vs. 10), Sugar (1.5 vs. 2), and Protein (22.5 versus 21).

However, if you include calories between the Simply Protein bars and Kirkland Signature (225 vs. 190) and Sodium (420 vs. 190), the Kirkland Signature is a healthier protein bar than the Simply Protein bar. In addition, they are comparably priced online for individual boxes. However, a box of Kirkland provides 1200 grams compared to 600 grams of Simply Protein. 

Number Four.

Staying with the extrapolation approach, the Ready Chocolate bar is larger than all but the Kirkland bar and has a little less sodium (160 to 190) and the same amount of fat as Kirkland (7 to 7). They are somewhat similar except when you look deeper. Kirkland has more protein (21 to 15), less sugar (2 to 10), more fiber (10 to 7), and fewer calories (190 to 200). Even though The Ready Chocolate bar is gluten-free, it is more competitive against most of these top 5 bars except for the Kirkland Signature.

The last comparison is Pure Protein versus Costco's brand (Kirkland). They are fairly comparable in most categories, although Kirkland has a little less sodium (190 to 200), more carbs (22 to 17), and more fiber (10 to 1). In addition, the Kirkland Signature bar is

20% larger in volume with a price savings of 25 cents per bar. having said this, the Pure Protein bar should also be ranked higher than fifth.

My conclusion of the "Top 5 Protein Bars at Costco," based on science and actual experimentation, the Kirkland Protein Bars are the most nutritious protein bars at Costco. In addition, they contain the most amount of grams (60) and are the least expensive bars overall at $1.20 per bar.

Nutritional information

Using Kirkland as a base point, I extrapolated what nutritional value each protein bar would contain if it contained the same volume as a Kirkland Signature bar which is 60 grams. I then went through all the nutritional information to select the top two bars for each category (highlighted in yellow).


Based on the website, 'Eat This, Not That,' lists the top five most nutritional protein bars that someone can buy at Costco. You'll see the results above if you extrapolate all bars to be comparable to Kirkland's Signature protein bar. Not even considering the price (Kirkland is considerably the least expensive), you will find that Costco's brand ranks the highest among all five bars (only including the top two in each category). Interestingly, this website considers the RX Bars as the most nutritious. Based on my comparison, besides the Kirkland bar, several others have more attractive nutritional levels than the RX Bar.

Writer's Note: This article was published in late October of last year. Therefore, the information that has been discussed should not vary in any measurable amount.

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