A growing set of studies show that an organic diet is associated with reduced levels of urinary pesticide analytes. However, with the exception of one pilot study of two individuals, diet intervention studies to date have not analyzed glyphosate, the most commonly used herbicide in the United States and globally.

The aim of the study was to investigate the impact of an organic diet intervention on levels of glyphosate and its main metabolite, AMPA (aminomethyl phosphonic acid), in urine collected from adults and children.

As a method, we analyzed urine samples from four racially and geographically diverse families in the United States for five days on a completely non-organic diet and for five days on a completely organic diet (n = 16 participants and a total of 158 urine samples).

Results: Mean urinary glyphosate levels for all subjects decreased 70.93% (95% CI -77.96, -61.65, p<0.010) while mean AMPA levels decreased by 76.71% (95% CI -81.54, -70.62, p < 0.010) within six days on an organic diet. Similar decreases in urinary levels of glyphosate and AMPA were observed when data for adults were examined alone, 71.59% (95% CI -82.87, -52.86, p < 0.01) and 83.53% (95% CI -88.42, -76.56, p < 0.01) and when data for children were examined alone, 70.85% (95% CI -78.52, -60.42, p < 0.01) and 69.85% (95% CI -77.56, -59.48, p < 0.01).

Conclusion: An organic diet was associated with significantly reduced urinary levels of glyphosate and AMPA. The reduction in glyphosate and AMPA levels was rapid, dropping to baseline within three days. This study demonstrates that diet is a primary source of glyphosate exposure and that shifting to an organic diet is an effective way to reduce body burden of glyphosate and its main metabolite, AMPA. This research adds to a growing body of literature indicating that an organic diet may reduce exposure to a range of pesticides in children and adults.