Carbs In Cornstarch: Is Cornstarch Keto?

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With its fine, powdery consistency and neutral flavor, cornstarch is a popular gluten-free thickening agent in foods like soups, stews, pudding, sauce, gravy, and more, as well as a popular ingredient in baking. Most recipes only require a small amount of cornstarch to work — but is cornstarch keto? Let’s take a closer look at carbs in cornstarch and keto friendly alternatives.

Looking for cornstarch replacements? See a full list of cornstarch substitutes (many of which are keto friendly!).

New to counting carbs or keto? Learn the keto diet basics here and grab my printable keto cheat sheet system to make it easy.

Is Cornstarch Keto Friendly?

Sorry, cornstarch is not keto friendly. Like fresh corn on keto, it contains high carbohydrates per serving and can easily kick you out of ketosis.

Is cornstarch low carb, though? It might work with a low carb diet, but check your macros to know for certain.

How Many Carbs In Cornstarch?

Does cornstarch have carbs? It certainly does, and in fact, cornstarch macros are entirely carbs. Carbs in cornstarch (1 tbsp) add up to 7 grams total carbs [*].

How many net carbs in cornstarch? Since it has no fiber, cornstarch net carbs still add up to 7 grams for a tablespoon.

Serving Size	Total Carbs	Net Carbs
1 tablespoon	7g	7g

Cornstarch Nutrition

A closer look at cornstarch shows why this fine powder (along with other starches like arrowroot flour) may work for a low calorie diet but does not align with a keto plan or provide many health benefits. Here are the full nutrition facts for a tablespoon of cornstarch:

• 30 calories
• 0 grams of fat
• 0 grams of protein
• 7 grams of carbs
• 0 grams of dietary fiber

While a serving or two is likely all you need across an entire recipe, its lack of fiber and high glycemic index can spike blood sugar levels [*]. Larger servings of cornstarch contain traces of copper, selenium, iron, and manganese, but you won’t find great quantities of vitamins and minerals in the average serving size.

Keto Substitutes For Cornstarch

Ounce for ounce, carbs in cornstarch make it a less-than-ideal ingredient choice. Not to worry, though — you can still find low carb substitutes for cornstarch to use as thickeners in keto recipes. While some alternatives like wheat flour would not be keto, either, there are others (like xanthan gum, guar gum, chia seeds, flaxseeds, coconut flour, glucomannan powder, pureed veggies, and more) that can work with modifications to amount or technique. See the full list of cornstarch substitutes here!

Conclusion: Can You Have Cornstarch On Keto?

Given the high carbs in cornstarch, you should avoid it on a ketogenic diet, especially if weight loss is your goal. With a wide variety of cornstarch substitutes, you can easily find a lower-carb thickener for your favorite recipes.