Are McDonald’s fries gluten-free celiac?

Quick Answer

McDonald’s fries are not gluten-free or safe for those with celiac disease. While the fries themselves do not contain gluten, they are cooked in oil that is shared with breaded chicken items which can cause cross-contamination. There is a risk of trace amounts of gluten getting into the fries during the cooking process.

Are McDonald’s Fries Gluten Free?

McDonald’s french fries are not gluten-free and should be avoided by those with celiac disease or non-celiac gluten sensitivity. While McDonald’s fries do not contain wheat, barley, rye or other gluten sources, there is a risk of cross-contamination during the cooking process.

McDonald’s uses a dedicated fryer for their french fries. However, according to McDonald’s, the fryer oil is also used to cook Chicken McNuggets, Chicken Selects and fried fish sandwiches which all contain gluten from breading or batter. Sharing oil between gluten and gluten-free items can transfer trace amounts of gluten into the otherwise gluten-free food.

For highly sensitive individuals, even small amounts of cross-contact gluten can trigger symptoms. The level of gluten transferred through shared oil is generally uncertain and can vary between locations. For those with celiac disease or who are extremely gluten intolerant, the potential trace gluten contamination poses too much of a risk.

McDonald’s Fry Ingredients

McDonald’s french fries have three main ingredients:

  • Potatoes
  • Vegetable oil (canola oil, corn oil, soybean oil, hydrogenated soybean oil)
  • Dextrose (natural sugar)

None of these ingredients contains gluten. However, the potential for cross-contact gluten exposure occurs during the cooking process when the fries and breaded fried items share the same fryer oil.

McDonald’s Fry Cooking Process

Here is the process McDonald’s uses to make their french fries:

  1. Potatoes are peeled, cut into shoestrings and rinsed.
  2. The cut fries sit in a solution of water and dextrose to remove starch.
  3. Fries are partially fried in vegetable oil for 1-2 minutes at a low temperature.
  4. Fries are frozen and shipped to McDonald’s locations.
  5. At the restaurant, fries are deep fried in oil for 3-4 minutes at 365°F.
  6. Fries are salted and served hot.

It is during the final frying at restaurants that potential cross-contact can occur. The same fryer oil is used for breaded chicken items before cooking the fries. The shared oil may pick up traces of gluten-containing breading that can then transfer to the fries.

Can Trace Gluten in Fries Impact People with Celiac Disease?

Yes, even tiny amounts of gluten transferred through shared cooking oil can trigger symptoms and intestinal damage for those with celiac disease. Celiac disease is a serious autoimmune disorder that causes damage to the small intestine when gluten is ingested. The condition requires a strict 100% gluten-free diet.

For individuals with celiac disease, trace gluten exposure can lead to:

  • Gastrointestinal distress (diarrhea, constipation, nausea)
  • Bloating, gas, stomach pain
  • Fatigue, headaches
  • Skin rash (dermatitis herpetiformis)
  • Mouth sores
  • Joint pain
  • In children, failure to grow and develop

Repeated contamination of even tiny amounts of gluten can also cause ongoing intestinal damage for those with celiac. This leads to malnutrition and a failure to heal the intestinal villi which are finger-like projections that absorb nutrients.

The revocation limit set by the FDA for labeling gluten-free foods is 20ppm (parts per million). However, studies show that amounts below this level can still cause issues for celiac patients. One study found that 50mg of gluten per day (equivalent of about 5ppm) could cause damage to intestinal villi in those with celiac disease.

Since the exact amount transferred through shared fryer oil is unknown, McDonald’s fries should be avoided by those with celiac disease or gluten intolerance.

What About Non-Celiac Gluten Sensitivity?

Individuals with non-celiac gluten sensitivity (NCGS) or those avoiding gluten for other reasons also need to avoid McDonald’s french fries. While the reaction may not be as severe as in celiac disease, trace gluten exposure can still cause gastrointestinal symptoms, fatigue, neurological issues and more.

Those with Irritable Bowel Syndrome (IBS) often identify gluten as a trigger as well. Overall, it is best for anyone with a need or preference to be gluten-free to steer clear of McDonald’s fries.

Are McDonald’s Fries Cooked in Beef Tallow?

McDonald’s fries were originally cooked in a mixture of 93% beef tallow and 7% cottonseed oil after being partially fried and frozen at the factory. However, McDonald’s switched the oil formulation in 1990 amid public health concerns over excessive trans fats, cholesterol and saturated fat.

Today, McDonald’s fries are cooked entirely in vegetable oil. The oil blend varies by location but typically includes some combination of canola oil, corn oil, soybean oil and hydrogenated soybean oil. McDonald’s also has a dedicated fryer system to avoid cross-contact with meat items.

So while McDonald’s fries were not always vegetarian, they no longer contain any beef tallow or other animal products. However, the potential for cross-contact with gluten-containing items during frying makes them unsuitable for a strict gluten-free or celiac diet.

Are McDonald’s Fries Safe for a Gluten-Free Diet?

No, McDonald’s fries are not safe for a gluten-free or celiac diet. While the ingredients themselves are free of gluten, the shared fryer oil used to cook breaded chicken items creates a cross-contact risk.

McDonald’s has confirmed their fryer oil is used for the following gluten-containing products:

  • Chicken McNuggets (breaded)
  • Chicken Selects (breaded)
  • Filet-O-Fish (breaded)

Those adhering to a gluten-free diet for medical reasons like celiac disease should avoid any food prepared in shared fryer oil. The unknown level of gluten cross-contact makes McDonald’s fries an unsafe choice.

Gluten-Free Alternatives to McDonald’s Fries

Here are some gluten-free restaurant french fry options:

  • In-N-Out: fries are fried in a dedicated fryer
  • Five Guys: fries are gluten-free but have cross-contact risk during service at the fry station
  • Smashburger gluten-free bun + fries (fryer cross-contact still a risk)
  • Chipotle fries
  • Wendy’s baked potato as a lower risk option
  • Chick-fil-A waffle fries and hash browns are gluten-free

Those with celiac disease know that maintaining a strict gluten-free diet when dining out takes proper precautions and research. Fries, onion rings, and other fried sides often have a higher chance of gluten cross-contact even when made from gluten-free ingredients.

Are Hash Browns and Apple Pie Gluten-Free at McDonald’s?

No, McDonald’s hash browns and apple pie are also not gluten-free due to cross-contact risks. Additionally, the apple pie contains wheat flour in the pie crust.

Here are some other menu considerations for those avoiding gluten at McDonald’s:

Gluten-Free Menu Items

  • Plain hamburger patties
  • French fries (with gluten cross-contact)
  • Apple slices
  • Salads without croutons
  • Vanilla soft serve cone
  • Coffee, tea, fountain drinks
  • Hash browns (with gluten cross-contact)

Not Gluten-Free

  • Burgers with buns
  • McMuffins
  • Chicken nuggets and selects
  • Pies and baked goods
  • Breaded Items
  • Oatmeal
  • Gravy
  • Salads with croutons

It is always advisable for the highly gluten-sensitive to verify ingredients and preparation methods by checking with restaurant managers. In general, plain grilled meats without sauces or buns are the safest choice at any fast food restaurant.

Can You Request Gluten-Free Fries at McDonald’s?

Those adhering to a gluten-free diet may wonder if they can request freshly made fries in a dedicated fryer. Unfortunately, this is not an accommodation McDonald’s offers.

All McDonald’s restaurants cook fries in the same shared oil as the breaded menu items. There are no designated gluten-free fryers. The supply chain and high volume cooking process is not set up in a way that allows for custom orders.

Your only optons are to avoid the fries entirely or to accept the unknown level of cross-contact gluten exposure if you choose to consume them.

Are McDonald’s Fries Gluten-Free in Other Countries?

McDonald’s frying practices can vary slightly in different countries. However, since the menu items are fairly consistent worldwide, most McDonald’s locations globally have similar concerns over cross-contact with breaded foods when frying.

In some countries like the UK, McDonald’s states their fries may not be suitable for those with certain food allergies due to sharing equipment. They recommend checking directly with your local restaurant on their procedures.

It seems unlikely you will find significantly safer procedures regarding gluten cross-contact at McDonald’s internationally. Your own personal tolerance levels would determine if you feel comfortable consuming fries potentially cooked in shared oil overseas or not.

Why Are McDonald’s Fries Not Gluten-Free?

To summarize, McDonald’s fries contain no wheat, barley, rye or gluten-based ingredients. So why exactly can’t they be considered gluten-free?

It comes down to the high risk of cross-contact during the cooking process. Since the same fryer oil is used for breaded chicken menu items, trace amounts of gluten can get transferred to the fries.

While the fries have no intrinsic gluten, the cooking method and shared equipment make it impossible to guarantee no exposure. Even tiny amounts can sicken those highly sensitive, so McCarthy’s cannot claim their fries are gluten-free or safe for celiac diets.

Frying Oil Gluten Cross-Contamination Explained

When breaded or battered items containing wheat flour are fried in oil, minuscule bits of breading can come off and get absorbed into the oil. Later, when plain fries are fried in that same oil, those remnants of gluten can stick to the fries and infect them as well.

Even thorough filtering between frying different products cannot remove 100% of microscopic transferred gluten. Thus “gluten-free” items can pick up trace amounts when sharing oil with breaded menu items.

This oil transfer poses a risk to those who need to avoid any exposure to gluten. That is why true gluten-free restaurants use completely dedicated fryers to prepare safe french fries and other items.


McDonald’s french fries are not gluten-free or safe to eat for those with celiac disease or on a strict gluten-free diet. While the potatoes themselves contain no gluten, the shared frying oil exposes the fries to cross-contact with ingredients like wheat-flour breading.

McDonald’s cannot guarantee the fries will be free of trace gluten transferred from fried chicken menu items. Those with medical conditions requiring a gluten-free diet should avoid McDonald’s fries and other shared-fryer foods due to uncertainty around precise gluten levels.

Choosing gluten-free menu items like plain hamburger patties without buns or sauces is a safer option at McDonald’s. Being vigilant about cross-contamination risks is key for those with celiac disease trying to navigate fast food restaurants.

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