NEW YORK (AP) -- Whole Foods says all products in its North American stores will have labels disclosing whether they contain genetically modified ingredients by 2018.

The company says it's the first national grocery chain to set such a deadline for labeling foods that contain genetically modified organisms, or GMOs.

Whole Foods Market Inc. notes that it has been working with suppliers for years to source products that don't have GMO ingredients. It says it currently sells more than 3,000 GMO-free products, more than any other retailer in North America.

The use of GMOs has been a growing issue, with health advocates pushing to require labels on GMO products.

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