When many people think of "flour," it's easy to assume that "flour" is equivalent only to "wheat flour," which would mean that all flour contains gluten and therefore aren't safe on a gluten-free diet.

However, luckily for those on a gluten-free diet, this assumption is wrong: not all flour contains wheat. Actually, there are many types of gluten-free flour that are safe for those on a gluten-free diet to eat.

Types of Gluten-Free Flour

Gluten-free flour options include:

Buckwheat flour
Finely ground cornmeal
Tapioca flour
Rice flour
Coconut flour
Millet flour
Sorghum flour

You also can find gluten-free flour blends intended as direct replacements for wheat flour in recipes. Products include:

Better Batter Gluten-Free Flour
Bob's Red Mill Gluten-Free 1-to-1 Baking Flour
Cup4Cup Gluten-Free Flour
King Arthur Gluten-Free Flour
Pamela's Products Gluten-Free Artisan Flour Blend

It's true, however, that the vast majority of foods made with flour will not be gluten-free. So read on to learn how to identify foods made with gluten-free flour.

Wheat Flour Contains Gluten

The U.S. Food and Drug Administration allows manufacturers to list wheat flour as "flour" on food labels. In fact, the word "flour" is reserved for flour that's made from wheat. This can make it tricky for those looking for gluten-free options, as the word "wheat" may not be on a food label that contains wheat flour.

Wheat flour—the only type allowed to be listed as just "flour" on ingredients labels—definitely does contain gluten (gluten is a protein found in the grains wheat, barley, and rye). If all you see on a food label is the word "flour," assume that it's wheat flour.

Wheat flour also can be listed on a package as "whole wheat flour" or "wheat flour"—both of those also contain gluten, so the product can't be eaten as part of a gluten-free diet. However, if you see the word "flour" on an ingredients list preceded by a word like "rice" or "corn," that food may be gluten-free and safe for you to eat.

Flour Isn't Always Wheat (But It Usually Is)

Even though flour most often is made from wheat, flour doesn't have to be made from wheat—by definition, "flour" is simply a powdery substance made by grinding a starch. The starch is usually a grain, but not always.

You can make flour from almonds, chestnuts, and even potatoes in addition to different types of grains, and many companies sell these specialty flours. People following a low-carb diet often use almond flour in place of grain-based flours, for example.

Flours made from a starch other than wheat, barley, or rye are usually gluten-free (but not always). If a label says "gluten-free" it complies with the Food and Drug Administration's gluten-free guidelines and should be safe for those on gluten-free diets to eat.

When you're reading ingredient labels, you'll see that flour made from anything other than wheat always will be identified as such—for example, it will be listed as "rice flour," "soy flour," "chestnut flour," "almond flour" or "(fill in the blank) flour" instead of just as "flour."

Choose Your Alternative Flours Carefully

While these alternative flours are usually gluten-free, they're not always safe on a gluten-free diet due to gluten cross-contamination in processing. The equipment to harvest and mill coarse grains or seeds into flour is pretty expensive, and so farmers and manufacturers frequently use the same equipment to process both gluten-containing and gluten-free ingredients.

When that occurs, naturally gluten-free ingredients can be cross-contaminated with gluten during harvesting or processing. That may mean they will contain enough gluten to make them unsafe for someone with celiac disease or non-celiac gluten sensitivity to consume.

Also, some products that use alternative flours as ingredients also include gluten as another ingredient—to eat gluten-free, you always need to check ingredients carefully.

A Word From Verywell

Of course, many foods made with these alternative flours are aimed directly at the gluten-free market—and they'll display the words "gluten-free" prominently on the package, which means they should be safe on the gluten-free diet.

The bottom line is, if you see the word "flour" on a food label, you need to read further before you can tell if the food contains gluten or not. If the ingredients label provides no detail other than something like "flour, sugar, yeast, shortening" then you should assume that this food contains gluten.