"The bottom line is that how you grow food, how it's fertilized, impacts the nutritional quality of it,” Benbrook said.

The study is the largest ever of its kind, he said, and it shows organic fruits, vegetables and grains contain 20 percent to 40 percent more antioxidants than non-organic, fewer pesticides and half the toxic heavy metal cadmium.

"It's like consuming 1 to 2 extra servings of fruits or vegetables a day, in terms of the antioxidants,” Benbrook said.

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Sandy Sessums said she isn't sure whether it's healthier to eat organic, but she knows nonorganic has ingredients she doesn't want. 

“We want all the chemical use out of it,” Sessums said.