Sulforaphane.us.com

C6H11NOS2 MW 177.29 CAS 4478-93-7 An isothiocyanate

Sulforaphane is not in broccoli.

It forms the moment the plant is cut, chewed or blended. Nearly everything that matters about getting a useful dose follows from that one fact.

The conversion

How sulforaphane forms Glucoraphanin, stored in intact plant tissue, is hydrolyzed by the enzyme myrosinase when the tissue is damaged. The reaction releases glucose and a sulfate group, and the remainder rearranges into sulforaphane. Glucoraphanin stored intact, inert O HO OH OH HOH2C S N OSO3− S O CH3 myrosinase released by cutting, chewing, blending − glucose − sulfate Sulforaphane formed only on damage H3C S O N S isothiocyanate group
Intact broccoli contains no sulforaphane. It stores glucoraphanin in one compartment and the enzyme myrosinase in another. Damage the tissue and the two meet: myrosinase cuts the sugar away, the fragment loses its sulfate group and rearranges, and sulforaphane exists. This is why chopping and resting matters, why boiling destroys the yield, and why two supplements with identical labels can deliver very different amounts. Structures are drawn in skeletal notation; the sugar is a Haworth projection and stereochemistry is not shown.

Where to start

Seven sections, each covering one part of the subject. The dose and food pages answer the practical questions; the chemistry and research pages show the working.

Broccoli sprouts

The richest food source, and the easiest to grow.

 Foods

Which cruciferous vegetables deliver, and how much.

 Dosage

How much per day, and what the trials actually used.

 Benefits

Claim by claim, graded by the evidence behind it.

 Supplements

What the labels mean and where they mislead.

 Chemistry

Glucoraphanin, myrosinase, conversion, absorption.

 Research

Every registered trial, tracked and kept current.

 Data

Reference tables, sourced and kept current.

How this site handles evidence

Sulforaphane attracts more overstatement than almost any other food compound. A great deal of what circulates about it comes from cell-culture work or from trials of a dozen people, and gets repeated as though it were settled.

Every claim here names its source, and every page says what kind of study it rests on. Where the honest answer is that nobody has run an adequate human trial, the page says so. Reported sulforaphane yields vary by more than an order of magnitude between studies depending on the assay, so figures on this site always carry the method they came from.

More on sourcing, and who writes this, on the about page.