The USDA’s new labeling for genetically modified foods goes into effect Jan. 1. Here’s what you need to know.

The goal was to get rid of the patchwork of different labels for foods and ingredients that have been scientifically tinkered with, according to the U.S. Department of Agriculture. However, the move also puts a greater burden on consumers to do their homework to understand what the labels mean, food advocates say.

Foods that previously were labeled as containing “genetically engineered” (GE) ingredients or “genetically modified organisms” (GMOs) will now be labeled as “bioengineered,” or come with a phone number or QR code guiding consumers to more information online.

The changes are part of the USDA’s new ruleson controversial modified crops and ingredients. Previous labeling requirements were governed differently on a state-by-state basis. By providing a uniform, national standard for labeling bioengineered foods, “it avoids a patchwork of state labeling regulations,” a USDA spokeswoman said in a statement.

The move is universally confounding food safety advocate groups. Eating bioengineered foods poses no risk to human health, according to the National Academy of Sciences and the Food and Drug Administration. However, watchdog organizations say the new rules contain too many...