Food Contaminants
glyphosate alters human hormone levels
In plain terms: Does glyphosate disrupt human hormones?
Contested Food Contaminants 🔬 Includes disconfirming
Part of: 🔍 glyphosate
RefutedContestedStrong support
consensus score 0.20
Several studies find lower sex hormones in people with more glyphosate in their urine, but they cannot show which causes which, and most come from the same survey. Much of the animal evidence tested Roundup rather than glyphosate, and the other ingredients may be doing the work.
📅 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
4 support 1 contradict 0 tested null 17 mixed · 22 sources, 4 independent groups
What the evidence shows
Two independent NHANES analyses and one pregnancy cohort found urinary glyphosate associated with lower sex steroids and altered thyroid hormones, which is a consistent direction across human datasets. All are cross-sectional or correlational, none establish causation, and NHANES underlies three of them so they are not fully independent samples.
The evidence (22)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Stone AM et al 2025 · Reproductive sciences (Thousand Oaks, Calif.) | observational | supports | low | Narrative review of female-reproductive-toxicity literature (authors cite human cell lines and animal models, no quantitative synthesis): concludes GBH exposure increases oxidative stress and disrupts reproductive hormones, associating it w |
| Unicsovics M et al 2026 · study_type: observational | observational | contradicts | low | RESIDENTIAL/DIETARY biomonitoring, HUMAN, cross-sectional (endometrial cancer cases vs age/BMI-matched benign controls, serum+tissue glyphosate; n not given): serum/tissue glyphosate was elevated in high-grade endometrial cancer, but NO sig |
| Kayser GL et al 2026 · study_type: observational | observational | mixed | moderate | RESIDENTIAL/agricultural-proximity, HUMAN (n=507 adolescents, Ecuador ESPINA cohort; salivary hormones vs. crop-area proximity, not an individual glyphosate biomarker): greater crop area near homes was associated with lower testosterone and |
| Valentín-Cortés MA et al 2026 · study_type: observational | observational | supports | moderate | PRENATAL/DIETARY biomonitoring, HUMAN (n=752 pregnancies, PROTECT birth cohort, Puerto Rico; urinary glyphosate/AMPA, IQR-scaled associations): AMPA linked to 10.6% lower estriol (95% CI -18.1,-2.4) and glyphosate to 8.3% lower estriol (CI |
| Alcalá-Pérez MA et al 2025 · study_type: in-vitro | in-vitro | mixed | low | IN-VITRO (human breast-cancer cell lines MCF-7/T47D/MDA-MB-231/MCF-10A/12A; PROSPERO-registered SR of 7 in-vitro studies to Nov 2025, pure glyphosate vs GBH formulations distinguished): pure glyphosate showed weak ERα-mediated estrogenic ac TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Mohammadi K et al 2022 · Environmental science and pollution research international | animal | mixed | moderate | EXPERIMENTAL ANIMAL (meta-analysis of 8 rat studies; doses/route not pooled in abstract): glyphosate decreased testosterone (WMD -1.48 ng/mL, 95% CI -2.34,-0.61, p=0.001) and LH (WMD -2.03 mIU/mL, CI -3.34,-0.71, p=0.003); FSH decrease non- TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Riechelmann-Casarin L et al 2026 · study_type: animal | animal | mixed | moderate | EXPERIMENTAL ANIMAL (male C57BL/6J mice, Western diet, 6 months; glyphosate 0.05 mg/kg/day [~ADI] or 5 mg/kg/day [near NOAEL]): 5 mg/kg raised serum T3 and follicle size; the LOW dose (0.05 mg/kg, ADI-level) raised follicular-cell prolifera TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Peng B et al 2026 · study_type: mechanism | mechanism | mixed | low | MECHANISM (theoretical adverse-outcome-pathway review synthesizing prior in vitro/in vivo literature; no new data): proposes ERα activation, aromatase inhibition, and mitochondrial ETC disruption as molecular initiating events linking GLY/G TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Dal' Bó IF et al 2026 · study_type: in-vitro | in-vitro | mixed | low | IN-VITRO, FORMULATION (Roundup Original DI on human papillary/anaplastic thyroid carcinoma + normal thyroid cell lines, 6.5-6500 µg/L, 24-48h): 65 µg/L -- below current regulatory limits -- triggered proliferative responses in all models, p TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Teleken JL et al 2026 · study_type: animal | animal | mixed | low | EXPERIMENTAL ANIMAL, FORMULATION (C57Bl/6 mice, pubertal gavage 50 mg/kg/day GBH -- ~100x the EU ADI -- then adult high-fat diet): elevated plasma T3 and cortisol in obese GBH-exposed mice of both sexes, plus increased testosterone (males) TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Giommi C et al 2026 · study_type: animal | animal | mixed | low | EXPERIMENTAL ANIMAL, DIETARY-modeled (adult female zebrafish, 21 days; glyphosate at EU ADI [0.5 mg/kg/day], 5, and NOAEL [50 mg/kg/day]): highest dose raised cortisol/cortisone and disrupted oocyte-maturation/estrogen-receptor-signaling ge TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Mandour DA et al 2026 · study_type: animal | animal | mixed | low | EXPERIMENTAL ANIMAL, FORMULATION (Sprague-Dawley rats, oral Roundup 244 µL/kg/day, 14 days -- a high experimental dose, not dietary-relevant): Roundup group showed hormonal imbalance, inflammation, oxidative stress and cytoarchitectural dam TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Szentirmay A et al 2026 · study_type: observational | observational | mixed | low | DIETARY/background biomonitoring, HUMAN (n=50 women undergoing IVF; serum+follicular-fluid glyphosate ~0.04 ng/mL, no exposure source specified): glyphosate positively associated with serum/follicular estradiol (β=40.26, p=0.006; r=0.29, p= |
| Rana I et al 2023 · Chemosphere | mechanism | mixed | moderate | MECHANISM (systematic review of 175 in vivo/ex vivo/in vitro mechanistic studies, human AND animal, PubMed to Aug 2021, Chemosphere): the endocrine-disruption 'key characteristic' (KC8) showed strong, consistent evidence glyphosate modulate TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Branco SR et al 2025 · study_type: animal | animal | mixed | low | Narrative review of endocrine-disruption/testicular-toxicity mechanistic literature (content is animal/in-vitro-derived, not a human clinical synthesis): concludes glyphosate/AMPA disrupt the HPG axis and testosterone via oxidative stress a TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Kaboli Kafshgiri S et al 2022 · Reviews on environmental health | animal | mixed | low | EXPERIMENTAL ANIMAL, FORMULATION (systematic review, 14 studies in rodents/lamb/fish, GBH not pure glyphosate; dose/route varied by study): consistent histological ovarian/uterine changes and altered serum progesterone/estradiol, dose- and TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Gomez AL et al 2026 · study_type: animal | animal | mixed | low | EXPERIMENTAL ANIMAL, MIXED-EXPOSURE, PRENATAL (rat, propiconazole+glyphosate co-administered, 3.7 mg GLY/kg/day + 4 mg PRO/kg/day, gestation to weaning): reduced serum testosterone and prostate ESR2 in postpubertal male offspring, but glyph |
| Chai Z et al 2025 · study_type: observational | observational | supports | moderate | DIETARY/background biomonitoring, HUMAN (NHANES 2013-2016, urinary glyphosate; n not stated in abstract): glyphosate associated with reduced Free Androgen Index (β=-3.27, 95% CI -4.45,-2.10, p<0.001), partly mediated by serum cholesterol (1 |
| Al-Azzam A et al 2026 · study_type: animal | animal | mixed | moderate | EXPERIMENTAL ANIMAL, FORMULATION (GBH via drinking water, adult male Sprague-Dawley rats, 30 days; glyphosate-equivalent 55 µg/kg/day [~ADI-range] and ~6 mg/kg/day): dose-dependent HPG disruption -- testosterone/LH reduced at high dose, est TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Choudhary L et al 2025 · study_type: observational | observational | mixed | low | Narrative review of 28 studies (9 HUMAN, 3 in-vitro, 16 animal) through Dec 2024, glyphosate/GBH and thyroid: HUMAN studies showed MIXED findings -- some associate exposure with altered thyroid hormones, others null; ANIMAL studies (esp. pe |
| Hamdaoui L et al 2025 · study_type: animal | animal | mixed | low | EXPERIMENTAL ANIMAL, FORMULATION, PRENATAL/lactational (Kalach GBH, Tunisia; rat dams gavaged 0.07 mL diluted herbicide/day, offspring assessed postnatal day 14): offspring showed hypothyroidism, thyroid tissue necrosis, and phosphocalcic/b TEMPERED: preclinical (animal/in-vitro) evidence, retained in the ledger but not carrying a human-outcome headline; dosing is typically far above human exposure. |
| Wu WY et al 2025 · study_type: observational | observational | supports | moderate | DIETARY/background biomonitoring, HUMAN (NHANES 2017-2018, n=1532, urinary glyphosate vs. 10 serum sex hormones): higher glyphosate associated with lower AMH, androstenedione, estradiol, estrone, estrone sulfate, 17α-OH-progesterone, and pr |
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