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costco keto hamburger buns

Aldi's L'Oven Fresh Zero Net Carb Bread has been flying off shelves since fall 2019, so it was only a matter of time before more major retailers started adding keto-friendly carbs to their product line-ups.

As a follow-up to the Natural Ovens Keto-Friendly White Bread that's sold online ($5.29, naturalovens.com), @costcoguy4u discovered that Costco is now selling keto-friendly hamburger buns—just in time for peak grilling season.

The growth in options for keto bread is likely because compared to Atkins, paleo and Whole 30 (and pretty much every other diet on the planet), interest and participation in the high-fat, low-carb diet is climbing at a stratospheric rate, according to Kerry Insights. They estimate that U.S. consumers will spend about $6 billion more on keto food products by 2027.

If you've been around EatingWell for a bit, you know we're usually not keen on drastic diets, preferring moderation in all things. What is a birthday celebration without a slice of cake, after all?

Still, it's clear this diet and these breads aren't going anywhere, so we wanted to take a deep dive into what exactly makes this new Costco bread keto-friendly...especially considering the keto diet generally limits followers to 20 to 50 grams per day. (For reference, a slice of our homemade four-ingredient Best No-Knead Whole Wheat Bread that's packed with nutrition has a reasonable 23 carbs per slice.)

Peek at the package and you'll spy that one Natural Ovens Keto-Friendly Bun is said to have 90 calories, 3 grams of fat, 10 grams of protein and 1 gram of net carbs (they calculate that by subtracting the 25 grams of fiber from the 26 grams of carbs). The ingredients list includes "zero-net carb blend" of wheat starch, wheat gluten, oat fiber, protein isolate and inulin (a prebiotic fiber) as well as yeast, soybean oil, vinegar and a couple preservatives.

If you do the math according to macronutrient calories per gram, you might be confused as to why the nutrition facts don't quite line up.

  • 26 g carbs x 4 calories per gram = 104 calories

  • 10 g protein x 4 calories per gram = 40 calories

  • 3 g fat x 9 calories per gram = 27 calories

  • Total calories: 167 calories

"'Net carbs' are calculated under the assumption that fiber does not affect your blood glucose or insulin production the way that non-fiber carbs do. There's conflicting research on how accurate this is, as we still synthesize some calories from fiber, but it does affect your blood sugar minimally compared to other simple carbs," says Jessica Ball, M.S., R.D., a registered dietitian and assistant nutrition editor at EatingWell.

Research published in the journal Diabetes Spectrum suggests fiber generally contributes between 1 ½ to 2 ½ calories per gram, so claiming the fiber cancels out all of the carb calories, "could be inaccurate on their part," Ball adds. Oh yes, and it could also mean that you're kicking your body out of ketosis if more of those carbs actually "count."

All that fiber in one package might lead to tummy troubles later in the day as well. As you might recall, the dietary guidelines recommend 25 to 38 grams per day, depending on your gender and calorie intake.

"Eating too much fiber can lead to digestive distress and constipation, especially when consumed in bulk quantities like this. I would advise people to be weary of eating so much fiber in one sitting unless they know they are already eating a diet much higher in fiber than the recommended daily amount, as it can take your body time to adjust to significant increases in fiber intake," Ball says.

Instead of stocking up on several loaves of keto bread in an effort to cut carbs, Ball recommends aiming to integrate more minimally processed foods—both for your mental and physical wellbeing. So go ahead, pop that burger on a regular whole-wheat bun or tuck it inside lettuce leaves if you want an option that's lower in calories. (No funky math required.)

"There are several nutritious components of traditional whole wheat flour, like B vitamins, fiber, protein and energy that our body needs to function. When you start modifying it so significantly, you run the risk of losing many of the healthful aspects of the whole food," she says.

Plus a laser focus on counting macros can get in the way of a healthy, sustainable eating pattern. Restricting carbs heavily, especially the nutritions ones like veggies, fruits, legumes and whole grains, can lead to gaps in your nutrition and overall health, "as well as being mentally taxing in practice," Ball says.