Five states have put restrictions on food and beverages covered by Supplemental Nutrition Assistance Program (SNAP) benefits. The changes will go into effect on Thursday. Here’s what you need to know.

What foods and beverages are being restricted for SNAP benefits purchases?

Indiana, Iowa, Nebraska, Utah and West Virginia are five states enacting waivers prohibiting the purchase of certain items through SNAP starting Jan. 1. Changes will affect about 1.4 million people, according to The Associated Press.

Utah and West Virginia will ban the purchase of soda and soft drinks; Nebraska will ban soda and energy drinks; and Indiana will ban soft drinks and candy. In Iowa, restrictions will be put on soda and candy and certain prepared foods. Experts say the list remains vague and does not include which specific products are being affected.

“The items list does not provide enough specific information to prepare a SNAP participant to go to the grocery store,” Gina Plata-Nino, the SNAP director for the anti-hunger advocacy group Food Research & Action Center, wrote, according to The Associated Press. “Many additional items — including certain prepared foods — will also be disallowed, even though they are not clearly identified in the notice to households.”

Not having a complete list of the foods and beverages affected may present challenges in-store.

“It’s a disaster waiting to happen of people trying to buy food and being rejected,” Kate Bauer, a nutrition science expert at the University of Michigan, told The Associated Press.

Why are restrictions being put on SNAP benefits purchases?

The changes come as part of a push by Health Secretary Robert F. Kennedy Jr. and Agriculture Secretary Brooke Rollins, who have been advocating to cut foods considered unhealthy from the program.

“We cannot continue a system that forces taxpayers to fund programs that make people sick and then pay a second time to treat the illnesses those very programs help create,” Kennedy said in December.

The changes could cost U.S. retailers $1.6 billion initially and then $759 million each year, according to a report by the Food Industry Association. It’s also the first time changes have been made since the federal policy was enacted in 1964, then authorized in 2008, which stated SNAP benefits could be used for “any food or food product intended for human consumption” apart from alcohol and ready-to-eat hot foods.

Proposals to restrict SNAP purchases have been made in the past but were denied due to USDA research showing it would be costly and difficult to put in place as well as would not affect customers’ habits.