Are Potatoes Gluten-Free? Learn When They're Not Safe

Plain potatoes are gluten-free. However, certain potato dishes (for example, French fries and potatoes au gratin) may not be gluten-free, depending on how they're prepared. The more ingredients you add, the bigger the risk that potatoes will no longer be safe on the gluten-free diet.

Here are some common ways to prepare potatoes, and the potential gluten-related pitfalls of each.

Baked Potatoes

Plain baked potatoes are gluten-free in and of themselves. Preparing them at home and having a completely gluten-free kitchen is best, as baked potatoes in restaurants may not always be safe.

How to Make Gluten-free Baked Potatoes

If you prepare gluten-containing foods in your kitchen, you should not place baking potatoes directly on the oven rack, as that may introduce cross-contamination from gluten-filled rolls or pizzas that also were baked on that oven rack.

Gluten-free Baked Potatoes in Restaurants

You'll need to talk to ask your server to talk to the chef to find out how the potatoes are prepared. Baked potatoes you get in restaurants may be safe (they usually are, in fact), but you'll need to check with the chef who prepared them to be certain.

Some restaurants coat the skins in butter and flour to make them crispier, and some bake the potatoes in the oven directly on the oven rack with the rolls. Most restaurants should be willing to fix you a gluten-free baked potato baked in aluminum foil if their regular spuds are unsafe.

French Fries

French fries you make at home from scratch should be gluten-free. Also, many brands of prepared French fries are considered gluten-free. However, you're very likely to run into problems when ordering them in a restaurant or a fast food place.

How to Make Gluten-free French Fries

You can prepare them from fresh potatoes by slicing the potatoes thinly, tossing them with olive oil and your choice of seasonings, and then baking them in the oven at 425 degrees until crisp (usually between 30 and 45 minutes, depending on how thin you make your slices).

These healthy low-fat French fries (which you can make from potatoes, butternut squash, carrots, or even turnips) never disappoint. Alternatively, you can buy a brand of gluten-free French fries and follow the directions on the package.

Gluten-free French Fries in Restaurants

The problem with French fries in restaurants usually isn't the fries themselves—it's the oil they're cooked in. Restaurants typically share oil between fries and wheat-coated foods such as onion rings and chicken fingers, and this can introduce enough gluten cross-contamination to make you sick.

You'll need to ask in every restaurant if the fries are prepared in a shared fryer. You'll also need to steer clear of French fries with a crispy batter coating—the batter typically is made with wheat flour.

This guide to gluten-free fast food lists the chain restaurants and fast food outlets that serve fries that are safe to eat on the gluten-free diet.

Mashed Potatoes

Plain mashed potatoes made from scratch should be gluten-free, assuming you avoid cross-contamination in the kitchen. Pre-made mashed potatoes may or may not be gluten-free, and the same goes for mashed potatoes in restaurants.

How to Make Gluten-free Mashed Potatoes

It's quite possible to make delicious, healthy mashed potatoes that also are gluten-free. Mashed potatoes generally consist of potatoes plus milk and butter which are safe on the gluten-free diet. Add some gluten-free spices to spice them up, or blend in some gluten-free cheese.

If you want the convenience of store-bought mashed potatoes, several brands of instant mashed potatoes are considered gluten-free to less than 20 parts per million (ppm), including Betty Crocker Potato Buds, Idaho Spuds Naturals line, and Hungry Jack Instant Mashed Potatoes. Simply Potatoes products, which you'll find in the refrigerator section at the store, also are considered gluten-free.

Gluten-free Mashed Potatoes in Restaurants

Most restaurant-made mashed potatoes are gluten-free. However, you'll need to find out from the chef in order to be certain.

Stuffed Potatoes

Stuffed potatoes may or may not be gluten-free, depending on the ingredients used and whether they're prepared in a safe manner. 

How to Make Gluten-free Stuffed Potatoes

Most stuffed potato recipes would be easy to make gluten-free as they didn't contain any obvious gluten-containing foods, such as bread. But most contain ingredients like bacon, cheese, and instant soup mix that come in both gluten-free and gluten-filled versions.

Choose your ingredients carefully if you make stuffed potatoes at home. You'll need to make sure to use gluten-free bacon and other safe ingredients, such as gluten-free sour cream (Daisy brand sour cream is safe). 

Gluten-free Stuffed Potatoes in Restaurants

Again, this is a matter of double-checking the ingredients used to make the potatoes. Some chain restaurants, such as Wendy's, do offer gluten-free stuffed baked potatoes.

Potato Skins

If you're making your own fried potato skins, you'll need to check all the ingredients. Potato skins are a common menu item in restaurants, where shared (and cross-contaminated) fryers are the main problem for those of us who are gluten-free.

Unfortunately, most restaurants fry their potato skins in fryers shared with breaded items like mozzarella sticks and onion rings, which makes them unsafe for those people with celiac disease or non-celiac gluten sensitivity. The bottom line here: Tread super-carefully when it comes to fried potato skins.

Potatoes Au Gratin

Recipes for potatoes au gratin generally are not safe; they almost always call for flour as a thickener, plus have a breadcrumb topping. Of course, you can make them with a gluten-free scalloped potato recipe.

But you should avoid potatoes au gratin and other potato casseroles when dining out or when at a friend's house, or at the very least check for gluten-containing ingredients before eating. Also, it would be hard to find a safe frozen version of potatoes au gratin in the supermarket, so you'll probably want to steer clear of those as well.

Potato Bread

Conventional potato bread you can buy in the store contains wheat flour, usually as the first or second ingredient. It's best to avoid potato bread or make your own from a gluten-free recipe.

Potato Flour and Potato Starch

These potato flour products appear as ingredients in numerous gluten-free recipes, and you easily can find safe sources for them. Bob's Red Mill, for example, has a dedicated gluten-free facility and offers many products that are certified gluten-free by the Gluten Free Certification Organization. The company also tests for trace gluten to below 20 parts per million, or GF-20 levels.

A Word From Verywell

Protect your health by being diligent in checking for gluten in recipes and prepared foods if you have celiac disease or non-celiac gluten sensitivity. Potatoes can be a delicious part of a gluten-free diet if you take those precautions to look for hidden sources of gluten.