One week of eating organic can dramatically reduce pesticide levels in the body, according to a recent study conducted by the Health Research Institute, Commonweal Institute, and Friends of the Earth. 

The group of researchers tracked the pesticide levels of four families across the United States. They took measurements after six days on a non-organic diet and again after six days on an organic diet.

The study, and a companion study published last year, found 16 different kinds of pesticides and chemicals in every participant. But after six days of organic eating, these compounds decreased an average of 60.5 percent—and some as much as 95 percent. Glyphosate, the main ingredient in Roundup and the most used pesticide in the world, dropped an average of 70 percent.

A study by agricultural economist Charles Benbrook finds that the use of glyphosate has spiked 15-fold globally since genetically modified, “Roundup Ready” crops were introduced in 1996. The percentage of Americans with traceable levels of glyphosate in their bodies rose from 12 percent in 1972 to 70 percent by 2014, according to researchers at the University of California San Diego.