Chipotle revealed over the weekend that it would immediately stop serving foods containing genetically modified organisms (GMOs). As of Monday, the fast-food chain made the switch (with one exception).

“This is another step toward the visions we have of changing the way people think about and eat fast food,” Chipotle founder Steve Ells told the New York Times of the announcement. “Just because food is served fast doesn’t mean it has to be made with cheap raw ingredients, highly processed with preservatives and fillers and stabilizers and artificial colors and flavors.”

Two years ago, the chain became the first restaurant to label which menu items had GMOs. Even then, Chipotle had the long-term intention of ridding itself of GMOs entirely. "Our goal is to eliminate GMOs from Chipotle’s ingredients, and we’re working hard to meet this challenge," the company said in a statement two years ago.

"For example, we recently switched our fryers from soybean oil to sunflower oil. Soybean oil is almost always made from genetically modified soybeans, while there is no commercially available GMO sunflower oil. Where our food contains currently unavoidable GM ingredients, it is only in the form of corn or soy.”

Chipotle abides by a Food With Integrity philosophy, which Ells described in a 2014 blog post as "a vision for continuous improvement of the ingredients that we source for the foods that we prepare and serve to our customers."

In an interview about Chipotle's full removal of GMOs on CNN Money, Ells said it's all about giving consumers the best food possible.

"Chipotle is really showing that there's a better way to do fast food," Ells explained. "They say these ingredients are safe, but I think we all know we'd rather have food that doesn't contain them. We want to make the old fast food model irrelevant. We want to make great ingredients and classic cooking techniques accessible to everybody."

What are GMOs?

A GMO is an organism whose DNA has been doctored by genetic engineering. As ATTN: pointed out in a piece about GMOs last year, through breeding humans have been genetically modifying plants and animals for ages. We breed different types of dogs so they have specific traits, or breed apples to make them sweeter.

The GMOs Chipotle is opting to exclude are food items genetically modified by scientists. who use biotechnology to alter the DNA.

Though GMOs have been called unsafe to consume by some, many scientists say there's nothing harmful about GMOs. The fear is that we do not know what introducing GMOs to the environment will do to both crops, animals, the soil, and our bodies in the long-term. One of the biggest issues with GMOs is that they're not properly labeled so that consumers who don't want to purchase food that contains GMOs have little way of knowing.

What Chipotle uses instead of GMOs

According to the New York Times, finding non-GMO oil was the trickiest challenge. Chipotle now spends extra money to make tortillas with non-GMO canola oil, which might prompt to company to increase food prices. The chain also uses sunflower to fry chips and tortillas, and the company will begin using rice bran oil to mix into rice and fry fajita vegetables. Additionally, Chipotle has decided to use non-GMO corn. The full transition to non-GMOs won't be hard for Chipotle, as the entire menu contains under 70 ingredients.

"The vast majority of our ingredients don’t come in a GMO variety, and we use lots of whole, unprocessed foods, so it was easier for us to do," Ells told the New York Times. However, Chipotle will continue to serve chicken and pork from animals whose diets include GMOs.