Evidence report · Gut, immune system and inflammation

Sulforaphane

Sulforaphane, from broccoli sprouts and other crucifers, switches on the Nrf2 pathway that drives the body's antioxidant and detox defenses. Fresh sprouts are the best source; supplements work only if they contain both glucoraphanin and myrosinase. Cooking destroys the conversion enzyme, which mustard seed powder can restore.

Verdict

Not enough evidence

Sulforaphane is worth taking.

1 source: 1 partly

1 source: 1 partly

1 source credited4 counted mentions28 episodes · 39 h4 checked quotesChecked against the tape 2026-03-23

Does it work?

Each claim gets one verdict, worked out from every counted mention. One dot is one source: a researcher or a study. Tap a dot to see its receipt.

positive partly neutral negative Each researcher and each study counts once per claim, however often they come up.

  1. Not enough evidence

    Sulforaphane is worth taking.

    1 source: 1 partly. Fewer than 3 sources so far.

    Researchers say

    1 partly

    Studies show

    No study counted yet.

    67 more not counted · see why
    We could not tell what position it takes on this claim. 25
    The study cited could not be identified. 13
    A host's remark inside an interview. 12
    We could not tell where the evidence comes from. 9
    We could not confirm who is speaking. 8
    Show the receipts from 1 source
    1. Jed Fahey Video · partly · 2 mentions

      on FoundMyFitness, at 1:14:57 · partly · Their own research

      “what we showed was a rather dramatic reduction in many of the symptoms of autism in about half of the subjects compared to placebos.”

      on FoundMyFitness, at 1:15:25 · partly · Their own research

      “Right, the n was small, the number of subjects was small, but it was a dramatic improvement.”

  2. Not enough evidence

    Sulforaphane activates the body's antioxidant and detox defenses.

    1 source: 1 partly. Fewer than 3 sources so far.

    Researchers say

    1 partly

    Studies show

    No study counted yet.

    51 more not counted · see why
    We could not tell what position it takes on this claim. 13
    The study cited could not be identified. 11
    We could not confirm who is speaking. 10
    A host's remark inside an interview. 9
    We could not tell where the evidence comes from. 8
    Show the receipts from 1 source
    1. Jed Fahey Video · partly · 2 mentions

      on FoundMyFitness, at 22:58 · positive · Their own research

      “we gave daily glucoraphanin and sulforaphane and monitored the upregulation of the this protective response”

      on FoundMyFitness, at 26:10 · partly · Their own research

      “we showed that the response was upregulated quickly and it was maintained”

5 more claims on dose, form and timing, each with its verdict and receipts, are in the full report.

How much, which type, and when?

Free with an account ↓
Dose
Form
Timing
Evidence
Verdict
Not enough evidence · 1 source: 1 partly

Is it safe for me?

5 risks to check before you start

  1. Sulforaphane does not harm the thyroid: no negative thyroid effects have been found, so the goitrogen worry is a myth (Jed Fahey, on FoundMyFitness).
  2. Broccoli sprouts can harbor bacteria if seeds aren't sterilized. Sterilize seeds with apple cider vinegar and soap before sprouting, and harvest by day 2-3 (Rhonda Patrick).
  3. Supplement quality varies enormously: many contain glucoraphanin without active myrosinase, so the body can't convert it well. Look for both glucoraphanin and myrosinase (Jed Fahey, on FoundMyFitness).
  4. Your gut bacteria affect conversion: people with less diverse gut bacteria may convert glucoraphanin less efficiently, from food and supplements alike (Jed Fahey, on FoundMyFitness).
  5. High doses from concentrated supplements may cause mild stomach upset. Broccoli sprouts are usually better tolerated.

Why do the sources disagree?

Built from every credited researcher and cited study on each claim.

On the claims above, no counted source takes a different side yet.

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About This Analysis

This report on Sulforaphane draws on 28 videos (39 hours analyzed) out of 3,700+ hours of recorded interviews with 370+ researchers and doctors, plus 18,100+ research studies. Every mention of a claim gets a stance, and the verdict is worked out from all of them, never written by hand.

The full report adds 8 key findings and the dose and protocol. It also has the verdict on every claim, a receipt for each mention, the risks to check, and what combines with it.

Frequently Asked Questions

How much sulforaphane should you take per day?
50-100 micromoles of sulforaphane daily, roughly 50-100g of fresh broccoli sprouts (Jed Fahey, on FoundMyFitness). Actual content varies a lot with genetics, growing conditions and preparation. Sprouts in a morning smoothie are one routine (Rhonda Patrick).
Broccoli sprouts vs sulforaphane supplement — which is better?
Fresh broccoli sprouts, which contain 20-100x more glucoraphanin than mature broccoli (Jed Fahey, on FoundMyFitness). Supplements can work, but quality varies enormously: many lack active myrosinase, the enzyme needed to convert glucoraphanin. Choose products with both.
Does sulforaphane help with detox?
Yes. It supports phase two liver detox, helping clear endocrine-disrupting chemicals from microplastics (Andrew Huberman). It increases excretion of carcinogens like benzene through Nrf2 (Rhonda Patrick), and raises glutathione in brain and plasma (Rhonda Patrick, on The Doctor's Farmacy).
What does sulforaphane do in the body (Nrf2)?
It is a potent natural activator of the Nrf2 pathway, which regulates over 200 genes for antioxidant defense, detox and anti-inflammatory response (Rhonda Patrick). Through Nrf2 it raises glutathione and helps clear carcinogens. In one study, the top 20% of cruciferous eaters had 22% lower all-cause mortality.
How do you get the most sulforaphane from broccoli?
Protect myrosinase, the heat-sensitive enzyme that makes sulforaphane (Rhonda Patrick). Eat crucifers raw or lightly steamed, heat sprouts to exactly 70C for 10 minutes to triple yield, or add mustard seed powder after cooking to boost bioavailability up to 4-fold.

Common Questions

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