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Diets · Food Contaminants

dietary pesticide exposure increases cancer risk

In plain terms: Do pesticides in food cause cancer?

Insufficient Diets

Part of: 🔍 pesticides in food

RefutedContestedStrong support
consensus score 0.26
⚖️ Thin evidence — read the needle loosely. The score shows which way the studies lean, but there are too few independent, high-quality ones to place it firmly. Expect this to move as better evidence arrives.

Eleven studies bear on this and not one of them answers it. Most are about farm workers, whose exposure is thousands of times higher than a shopper's. The rest use 'buys organic' as a rough stand-in for pesticide dose. Nobody has measured what people actually eat and followed them for cancer.

📅 Last reviewed: 2026-07-29

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: Population patterns (Observational)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

1 support 0 contradict 0 tested null 10 mixed · 11 sources, 1 independent group

What the evidence shows

There is no clean epidemiology isolating ordinary dietary pesticide intake and cancer risk. The one directly dietary well-powered study uses organic-versus-conventional consumption as a proxy for exposure rather than any measured residue dose.

The evidence (11)

SourceGradeStanceQualityFinding
Wan MLY et al
2022 · Critical reviews in food science and nutrition
observational mixed moderate PRISMA systematic review of 131 cohort/case-control studies on endocrine-disrupting chemicals (pesticides pooled with DDT/DDE, atrazine, dioxin, BPA, PFAS, phthalates) found some EDC exposures potentially elevate breast cancer risk, but exp
Maas SCE et al
2026 · Nature medicine
observational mixed high Nature Medicine study used DNA-methylation exposome risk scores to link the herbicide picloram to early-onset colorectal cancer (discovery cohort 31 EOCRC vs 100 LOCRC, adjusted P=4.4x10^-4; replicated in a meta-analysis of 9 CRC cohorts, 8
Kangkhetkron T et al
2024 · preprint
observational mixed moderate Case-control study (233 lung cancer cases vs 447 matched controls, Thailand) found lifetime herbicide/insecticide USE associated with higher lung cancer risk (Q3-Q4 use OR 2.20-3.99; dieldrin OR=2.56, 95% CI 1.36-4.81; chlorpyrifos OR=3.29,
Kondratiuk M et al
2026 · study_type: observational
observational mixed low National ecological time-series (Ukraine; pesticide-use data 2000-2021 vs cancer incidence 2014-2021) found some reproducible positive lag correlations (5-11y) for breast, colon, and lung cancer with herbicide/fungicide/insecticide use, but
Baudry J et al
2018 · JAMA internal medicine
observational supports high Large prospective NutriNet-Sante cohort (n=68,946, France, ~7y follow-up, 1340 incident cancers, most commonly breast) found higher organic-food consumption score (a lower-pesticide-residue diet proxy) inversely associated with overall canc
Karavasiloglou N et al
2022 · Current nutrition reports
observational mixed low Systematic review of 9 articles from 8 prospective cohorts found a modest inverse association between adherence to 'sustainable diets' and cancer incidence/mortality, but pesticide/organic-food exposure was only one of several bundled susta
Ataei M et al
2022 · Toxicology and applied pharmacology
mechanism mixed low Systematic review of mechanistic studies (2017-2022) argues pesticides (mainly organochlorines) may raise cancer risk via genetic/epigenetic mechanisms (p21, p53 induction, DNA methylation, histone modification), but is framed around mechan
Melanda VS et al
2022 · Toxics
observational mixed low Systematic review of 7 studies (4 case-control, 2 cross-sectional, 1 cohort) linking pesticide exposure to cancer AND congenital malformation explicitly states exposure sources were 'food, water, or exposure during agricultural work' - a mi
Honles J et al
2026 · study_type: observational
observational mixed moderate Country-scale ecological/spatial-Bayesian study (Peru, 31 pesticide active ingredients) found a spatial association between modeled environmental pesticide-exposure risk and cancer incidence, plus a distinct liver transcriptomic signature i
Ahmed OS et al
2025 · preprint
observational mixed low Preprint systematic review of 20 studies reports a significant association between pesticide exposure and bone tumors (osteosarcoma, Ewing's sarcoma), but exposure route is not reported/isolated (general agricultural/environmental populatio
Matich EK et al
2021 · Ecotoxicology and environmental safety
observational mixed moderate Systematic review of 139 articles on pesticide exposure and colorectal cancer found a near-even split of significant positive (39) and significant inverse (41) associations and explicitly could not conclude a direction; study populations we

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