Sulforaphane
Useful mainly for people seeking Nrf2/antioxidant enzyme activation; some signal in autism behavior.
Quick decision guide
May help most
people seeking Nrf2/antioxidant enzyme activation; some signal in autism behavior
Common dosing range
~10–30 mg sulforaphane (or glucoraphanin standardized to that) per day
When to expect effects
Days to weeks
Watch out for
Bioavailability varies widely; glucoraphanin without active myrosinase yields little sulforaphane
What is it
Sulforaphane is an isothiocyanate phytochemical formed when the enzyme myrosinase acts on glucoraphanin, a compound concentrated in broccoli and broccoli sprouts. It is a potent activator of the Nrf2 pathway, which upregulates the body's antioxidant and phase II detoxification enzymes. Most supplements supply glucoraphanin plus active myrosinase or pre-formed sulforaphane.
Is it worth it for you?
Use this as a quick fit check, not a diagnosis.
Worth considering if…
Probably skip if…
Evidence at a glance
| Goal | Effect | Best fit | Time |
|---|---|---|---|
autism spectrum behavior Limited Evidence | Modest in small trials | children and young adults with autism spectrum disorder, used adjunctively | Weeks |
Nrf2-mediated detoxification of airborne pollutants Limited Evidence | Increased urinary excretion of pollutant conjugates | adults with high environmental exposure to airborne benzene/acrolein | Days |
glycemic control in type 2 diabetes Limited Evidence | Small reductions in fasting glucose/HbA1c | people with type 2 diabetes and elevated fasting glucose | Weeks to months |
autism spectrum behavior
- Effect
- Modest in small trials
- Best fit
- children and young adults with autism spectrum disorder, used adjunctively
- Time
- Weeks
Nrf2-mediated detoxification of airborne pollutants
- Effect
- Increased urinary excretion of pollutant conjugates
- Best fit
- adults with high environmental exposure to airborne benzene/acrolein
- Time
- Days
glycemic control in type 2 diabetes
- Effect
- Small reductions in fasting glucose/HbA1c
- Best fit
- people with type 2 diabetes and elevated fasting glucose
- Time
- Weeks to months
Evidence for 3 uses
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
autism spectrum behavior
Supplement benefitA small placebo-controlled trial reported improvements in behavioral measures during sulforaphane (broccoli-sprout extract) supplementation, with regression after stopping. Subsequent trials have been small and mixed, so the effect is preliminary and not consistently replicated.
Bottom line: Preliminary signal for behavioral improvement in autism, but evidence is small and inconsistent.
Evidence is mixed
Some randomized trials show behavioral benefit while others find no significant difference; samples are small.
Nrf2-mediated detoxification of airborne pollutants
Biomarker supportIn a large randomized trial in a highly polluted area, broccoli-sprout beverage delivering sulforaphane increased urinary excretion of conjugates of benzene and acrolein, consistent with enhanced phase II detoxification. This is a biomarker of excretion, not a demonstrated reduction in disease risk.
Bottom line: Sulforaphane measurably boosts excretion of certain airborne toxicants, a biomarker effect rather than a proven health outcome.
glycemic control in type 2 diabetes
Biomarker supportA randomized trial of concentrated broccoli-sprout extract reported modest reductions in fasting blood glucose and HbA1c in patients with type 2 diabetes, especially among obese, dysregulated participants. Replication is limited and the effect is on glycemic biomarkers.
Bottom line: May modestly improve glycemic biomarkers in type 2 diabetes, but evidence is preliminary.
How it works
How to take it
What to track
4 commercial forms
Compare the main delivery options and what they’re best suited for.
Broccoli sprout extract with active myrosinase
Preferred supplement form. Look for products specifying active myrosinase or 'stabilized sulforaphane'.
Highest sulforaphane yield; the enzyme is essential for converting glucoraphanin.
Glucoraphanin-only extract
Less effective than products with myrosinase. Conversion is variable between individuals.
Lower sulforaphane yield; depends on gut bacteria for conversion.
Stabilized sulforaphane
Bypasses the conversion step but stability and shelf-life are challenges. Available in some premium products.
Direct sulforaphane is unstable; specialized formulations preserve it.
Fresh broccoli sprouts
3-day-old sprouts contain 20-50 times more glucoraphanin than mature broccoli.
Highest natural source of sulforaphane precursors and myrosinase together.
Safety
Know the common side effects, key cautions, and who should avoid it.
Common side effects
Who should avoid it
- people with known brassica/isothiocyanate intolerance
Pregnancy & breastfeeding
Not enough safety data in pregnancy; avoid concentrated supplements and rely on dietary intake.
Interactions
Food sources
| Food | Amount | %DV |
|---|---|---|
| Broccoli sprouts (1 oz) | Highest dietary source; significant sulforaphane equivalent | — |
| Mature broccoli (1 cup cooked) | Lower sulforaphane; cooking destroys myrosinase | — |
| Brussels sprouts (1 cup) | Moderate glucoraphanin content | — |
| Kale (1 cup cooked) | Lower content than broccoli | — |
| Cabbage, raw (1 cup) | Modest content; raw form preserves enzymes | — |
Broccoli sprouts (1 oz)
- Amount
- Highest dietary source; significant sulforaphane equivalent
- %DV
- —
Mature broccoli (1 cup cooked)
- Amount
- Lower sulforaphane; cooking destroys myrosinase
- %DV
- —
Brussels sprouts (1 cup)
- Amount
- Moderate glucoraphanin content
- %DV
- —
Kale (1 cup cooked)
- Amount
- Lower content than broccoli
- %DV
- —
Cabbage, raw (1 cup)
- Amount
- Modest content; raw form preserves enzymes
- %DV
- —
Choosing a product
What to look for on the label — and what to be skeptical of.
Look for…
Be skeptical of…
Frequently asked questions
How are broccoli sprouts different from regular broccoli?⌄
Broccoli sprouts (3-day old germinated seeds) contain 20-50 times more sulforaphane precursors than mature broccoli, making them the most concentrated dietary source.
Why is myrosinase important?⌄
Myrosinase is the enzyme that converts glucoraphanin into active sulforaphane. Without active myrosinase (destroyed by cooking), sulforaphane yield from supplements or cooked broccoli is much lower.
Does cooking destroy sulforaphane?⌄
Cooking destroys the myrosinase enzyme needed to form sulforaphane from its precursor. Light steaming (3-4 minutes) preserves more enzyme than longer or higher-heat cooking.
How much sulforaphane should I take?⌄
Studies use widely varying doses. A common range is 10-30 mg of sulforaphane equivalent daily from supplements, or several ounces of fresh broccoli sprouts.
Can sulforaphane prevent cancer?⌄
Observational studies link cruciferous vegetable consumption to reduced cancer risk, and preclinical research is strongly supportive. Rigorous human trials of supplementation for cancer prevention are limited.
References by claim
autism spectrum behavior
Nrf2-mediated detoxification of airborne pollutants
glycemic control in type 2 diabetes
Dwibedi et al., 2025 — PMC (2025) link
Track Sulforaphane with Pilora
Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.
Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.