Sulforaphane

• benzene 61%excretion increase · P≤0.01
• acrolein 23%excretion increase · P≤0.01
• 291participants · 12-week RCT

In a 12-week randomized trial in a heavily polluted region of Qidong, China, a broccoli-sprout beverage delivering glucoraphanin and sulforaphane raised urinary excretion of the glutathione-derived conjugates of inhaled pollutants, consistent with accelerated Phase II detoxification of carcinogens. The effect was significant for benzene and acrolein but, honestly, not for crotonaldehyde. This is a biomarker-excretion endpoint, not a disease outcome.

Reported effect: Statistically significant (P ≤ 0.01) increases in excretion of conjugates of benzene (61%) and acrolein (23%), but not crotonaldehyde, in the broccoli-sprout group vs placebo; n=291.

“Rapid and sustained, statistically significant (P ≤ 0.01) increases in the levels of excretion of the glutathione-derived conjugates of benzene (61%), acrolein (23%), but not crotonaldehyde, were found in those receiving broccoli sprout beverage compared with placebo.”

Source: PMID 24913818 · Egner 2014 · Cancer Prev Res (Phila)

• 6 trialsRCTs pooled
• 333participants

A 2025 meta-analysis pooling six randomized controlled trials reported that both 4-5 week and 8-10 week sulforaphane supplementation significantly lowered Social Responsiveness Scale scores versus placebo in children with autism spectrum disorder, with no significant difference in adverse-event incidence. The abstract reports the direction and significance but does not state a numeric pooled effect size, and the authors note efficacy across this literature remains controversial. Framed as a research finding, not a treatment.

Reported effect: Six trials involving 333 participants; both 4-5 weeks and 8-10 weeks of supplementation significantly decreased Social Responsiveness Scale scores vs placebo; no significant difference in adverse events (no numeric pooled effect size reported in abstract).

“Six trials involving 333 participants were included in the meta-analysis. Pooled results demonstrated that both 4-5 weeks and 8-10 weeks of sulforaphane supplementation significantly decreased the scores on the Social Responsiveness Scale compared to placebo controls. No significant difference was observed in the incidence of adverse events.”

Source: PMID 41275316 · Long 2025 · BMC Pharmacol Toxicol

• ALT 54.0→48.5 IU/Lmedian · P<0.05
• 8-OHdG 6.66→5.49ng/mg-creat · P<0.05
• 24 vs 28extract vs placebo

In a randomized, double-blind, placebo-controlled trial in Japanese men with fatty liver, two months of sulforaphane-precursor (glucoraphanin) broccoli-sprout extract significantly reduced serum ALT and gamma-GTP and lowered the oxidative-stress marker urinary 8-OHdG, while placebo did not. The 8-OHdG reduction correlated with the fall in liver enzymes, consistent with an oxidative-stress mechanism.

Reported effect: ALT median 54.0 (IQR 34.5-79.0) before vs 48.5 (33.3-65.3) IU/L after, P < 0.05; urinary 8-OHdG 6.66 (5.51-9.03) vs 5.49 (4.89-6.66) ng/mg-creatinine, P < 0.05; n=24 extract vs n=28 placebo.

“Dietary supplementation with BS extract containing SF precursor GR for 2 mo significantly decreased serum levels of liver function markers, ALT [median (interquartile range), before: 54.0 (34.5-79.0) vs after supplementation: 48.5 (33.3-65.3) IU/L, P < 0.05] ... The urinary level of 8-OHdG ... was significantly reduced in participants who had received BS capsules but not the placebo [before: 6.66 (5.51-9.03) vs after: 5.49 (4.89-6.66) ng/mg-creatinine, P < 0.05].”

Source: PMID 26604653 · Kikuchi 2015 · World J Gastroenterol

• -7.1%LDL-C · study 1 · p=0.011
• -5.1%LDL-C · study 2 · p=0.001

Two independent double-blind RCTs (130 volunteers total) found that eating 400 g/week of high-glucoraphanin broccoli for 12 weeks significantly reduced plasma LDL cholesterol versus standard broccoli. Important caveat: this signal comes from a glucoraphanin-rich whole-food broccoli diet, not from a free-sulforaphane supplement, so it should not be read as a free-SFN lipid claim.

Reported effect: Study 1 (n=37): LDL-C reduced 7.1% (95% CI -1.8% to -12.3%, p=0.011); Study 2 (n=93): LDL-C reduced 5.1% (95% CI -2.1% to -8.1%, p=0.001); combined reduction greater than standard broccoli (p=0.031).

“the HG broccoli diet reduced plasma LDL-C by 7.1% (95% CI: -1.8%, -12.3%, p = 0.011) ... the HG broccoli diet resulted in a reduction of 5.1% (95% CI: -2.1%, -8.1%, p = 0.001) ... When data from the two studies were combined the reduction in LDL-C by the HG broccoli was significantly greater than standard broccoli (p = 0.031).”

Source: PMID 25851421 · Armah 2015 · Mol Nutr Food Res

A 2024 study combined rat experiments with a human arm of 36 volunteers with abnormal glucose given a broccoli-seed tablet (42 mg/day sulforaphane) for 12 weeks. In the human arm, sulforaphane raised GLP-1, which correlated with reductions in blood glucose and HOMA-IR, proposed to act via a gut Bacteroides/Lactobacillus-SCFA-GLP1 axis. The abstract reports the direction for the human arm but no standalone numeric effect size, so the human glucose effect size is not extracted here.

Effect size: this study reports the direction of the finding but does not state a specific numeric effect size, so none is given here rather than estimated.

“SFN intervention increased the level of GLP1 in NAFLD patients, which was positively correlated with the reduction of blood glucose and HOMA-IR.”

Source: PMID 39045769 · Tian 2024 · Food Funct