Can an Organic Diet reduce an individual’s exposure to Pesticides?

Amelie Bieringer, M.Sc., Nutritionist

In the past, several studies have shown that diet is a major contributor to total pesticide exposure1,2. Exposure to pesticides is associated with a variety of health issues, such as low IQ3, an increase in attention and behavioural problems in children4, asthma5, cancer6, or body weight issues and metabolic disorders7. Compared to food from conventional farming, organic food has been shown to contain fewer pesticides8.
A study by Hyland et al. (2019) investigated whether exposure to pesticides can be reduced by switching from a conventional diet to an organic diet.

Study design:
The study involved4 American families (adults and children aged 3 years and older) who usually consume conventionally produced foods. The study lasted a total of 12 days. For the first 6 days, the families maintained their usual conventional diet. For the next 6 days, the families consumed exclusively organic foods. Urine samples were collected every day and analysed for 18 different pesticide metabolites and their original structures. Pesticide residues in the families’ urine samples were compared – before switching diets vs. after switching diets. A total of 158 urine samples from 16 subjects were analysed.  

The consumption of organic food could be related to a significant reduction in the excretion of pesticide metabolites and their original structures. This shows that an organic diet has reduced exposure to pesticides in children and adults. 

It should be noted that the study included only a small study population. Although exposure to pesticides was reduced in these subjects, no assessment was made regarding the clinical relevance of the reported levels of pesticides in the samples. Nevertheless, it is particularly important to protect vulnerable groups such as infants and children from exposure to pesticides and therefore to minimise their ingestion of pesticides with foods. The consumption of organic foods brings a significant benefit in this regard.   

1 Curl, C.L., et al., 2015. Estimating pesticide exposure from dietary intake and organic food choices: the Multi-Ethnic Study of Atherosclerosis (MESA). Environ. Health Perspect. 123, 475–483.

2 Riederer, A.M., et al., 2008. Diet and nondiet predictors of urinary 3-phenoxybenzoic acid in NHANES 1999–2002. Environ. Health Perspect. 116, 1015–1022.

3 Grunier et al, 2017. Prenatal Residential Proximity to Agricultural Pesticide Use and IQ in 7-Year-Old Children. Environ. Health Perspect 125, 5.

4 Butler-Dawso, J., et al, 2016. Organophosphorus pesticide exposure and neurobehavioral performance in Latino children living in an orchard community. Neurotoxicology 53, 165-172.

5 Raanan, R., et al. 2015. Early-life Exposure to Organophosphate Pesticides and Pediatric Respiratory Symptoms in the CHAMACOS Cohort. Environ. Health Perspect. 123,2.

6 Baudry J., et al. 2018 Association of frequency of organic food consumption with cancer risk findings from the NutriNet-Santé Prospective Cohort Study. Jama Internal Medicine.

7 Debost-Legrand, A., et al. 2016. Prenatal exposure to persistent organic pollutants and organophosphate pesticides, and markers of glucose metabolism at birth. Environ. Research.146.

8 Baransky, M., et al.: Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses. BJN, 2014.

9 Hyland et al. 2019. Organic diet intervention significantly reduces urinary pesticide levels in U.S. children and adults. Environ. Research. 171. 568-575.