What Is Guar Gum, and Is It Always Gluten-Free?

Guar gum is produced from the seeds of the guar plant, a plant in the legume family that's native to India. To make guar gum, manufacturers harvest the bean pods and process them to remove the husk and other parts of the seeds. The remaining purified powdery substance is guar gum.

Since guar gum is not made from one of the gluten grains (wheat, barley, and rye), it's considered a gluten-free food (assuming it was manufactured in a way that protected it from gluten cross-contamination).

In fact, in gluten-free baked goods, guar gum (along with xanthan gum) helps to thicken your batter and prevents the ingredients from separating. It also serves to trap air within the mix, which ultimately makes the batter rise when you bake. This makes the baked goods seem more like conventional baked goods made with wheat flour.

If you've been gluten-free for a while, you likely know that the gluten protein is the stuff in bread and other baked goods that gives it that springy, stretchy texture, and to make gluten-free baked goods anything like their gluten-y counterparts, you need something to replace the gluten. Guar gum can serve in that role.

You don't need much guar gum to do the job: Bob's Red Mill advises using up to 1/2 a teaspoon of guar gum per cup of gluten-free flour for cookies, up to two teaspoons per cup of flour for bread, and as much as a tablespoon for pizza dough (which, of course, is supposed to be thick and stretchy).

Sources of Gluten-Free Guar Gum

While guar gum—a product derived from the guar plant—is an inherently gluten-free ingredient, you still need to be careful to carefully source your guar gum to be certain it's free of gluten cross-contamination. (Unless a manufacturer is specifically targeting the gluten-free market, it might not be as careful as we need.)

The best way to ensure the gluten-free-ness of your guar gum is to purchase it from these sources, which specifically label their products gluten-free:

• Bob's Red Mill guar gum. If you've ever done any gluten-free baking, you're likely already familiar with Bob's Red Mill. Bob's offers guar gum in 8-ounce bags (given how little you need to use in recipes, that should last you a while), and it's part of the company's gluten-free line of ingredients. Be aware that Bob's processes its gluten-free oats (and other gluten-free grains, including corn) on the same equipment, so if you also can't eat oats, or if you have issues with corn, you may need to find another source for your guar gum.
• Judee's guar gum. This product, produced by Judee's Gluten-Free, is available on Amazon and elsewhere in 10 ounce packages. Judee's notes that it's packaged in a dedicated gluten-free and nut-free facility, so it could be a good choice for people who have nut allergies in addition to issues with gluten.
• NOW Foods guar gum. NOW Foods also sells guar gum in 8-ounce packages and specifically labels its guar gum "gluten-free." Although most of what NOW Foods sells (both food products and supplements) is gluten-free, the company does process its few gluten-containing products on the same lines. NOW Foods tests to ensure products contain less than 5 parts per million of gluten but acknowledges (in a very candid and transparent gluten-free statement) that gluten could remain at trace levels despite careful cleaning procedures. 

Guar Gum Digestive Effects

Guar gum contains the sugars galactose and mannose. If you're following a low-FODMAP diet in order to help treat irritable bowel syndrome, beware, as galactose is a form of FODMAP. Some FODMAP diet gurus advise using xanthan gum instead of guar gum.

Finally, manufacturers of ice cream frequently use guar gum as a stabilizer, and guar gum also is found in pharmaceuticals as a binder. A few laxatives have guar gum as their main ingredient, as guar gum is mainly soluble fiber.

A Word from Verywell

Some people—including people with celiac disease and non-celiac gluten sensitivity—report getting symptoms such as gas and abdominal pain when they ingest guar gum, even when they're using a gluten-free brand and not using very much of it. In these cases, the culprit likely is either very low-level gluten cross-contamination or a sensitivity to the guar gum itself.