- How prevalent is autism (autistic spectrum disorder or ASD) in the US?
In the US, 1 in 68 children now have ASD by the time they are 8 years old, the vast majority of them being male.
- What kind of improvements were observed in the study participants?
The group taking sulforaphane consistently experienced improved social communication and less irritability, lethargy, hyperactivity, and repetitive/ritualistic behaviors.
- How were these improvements measured?
We used three well-established, widely used psychometric behavioral tests to measure and quantify improvement. Both physicians and parents/caregivers (all unaware of whether the subject was getting sulforaphane or inactive placebo) were involved in the assessments.
- What was the source of sulforaphane used in the study?
We grew broccoli sprouts from proprietary, glucoraphanin-rich broccoli seeds, extracted the glucoraphanin using boiling water, allowed a natural enzyme from radish sprouts to convert glucoraphanin to sulforaphane, freeze-dried the extract, and encapsulated it to provide capsules with a specified sulforaphane content.
- Are there any foods that naturally contain sulforaphane?
Broccoli, a cruciferous vegetable, contains the precursor, glucoraphanin, and the enzyme myrosinase, which converts the glucoraphanin into its bioactive form, sulforaphane. However, there is enormous variability among supermarket broccolis in their content of glucoraphanin.
- I’ve heard that cooking broccoli reduces its nutritional value?
There are pros and cons (from a nutritional perspective) to cooking food.
In terms of the broccoli phytochemical involved in this study, cooking does destroy the enzyme that’s needed to convert the phytochemical present naturally in the plant (glucoraphanin) to sulforaphane.
- How much sulforaphane was used in the study?
The study used 18 milligrams of sulforaphane for a 150 lb person.
The broccoli sprout extract we used was well tolerated throughout the study. It was, after all, just a highly standardized form (extract) of a commonly consumed vegetable (broccoli).
- Are there products available that I can purchase which contain sulforaphane?
It would be difficult, though not impossible, to eat enough market stage broccoli to achieve the level delivered in the study.
To the best of our knowledge, there are no sulforaphane supplements currently available on the market with reliable, substantial, and well-validated levels.
The quantity of sulforaphane given to subjects is equivalent to the amount contained in between half a pound and a pound of market stage broccoli, or a few ounces of broccoli sprouts for a 150 lb person. However, conversion of glucoraphanin given in a supplement (extracted from the plant) to sulforaphane varies greatly, and averages only about 10%.
We are developing a product that delivers higher levels of sulforaphane for use in future clinical trials, but it is not available as a commercial product.
- What if I can’t get my child to eat broccoli?
- What is the role of the universities?
The authors are all university employees, and we are not in the business of making commercial products. This is why universities attempt to patent discoveries of their scientists, and license them to companies that will make such discoveries available to the public in a responsible manner.
Brassica Protection Products was founded by two of the study authors (Paul Talalay and Jed Fahey) more than 15 years ago to develop chemoprotective foods. Both Dr. Talalay and Dr. Fahey have relinquished all interest in, and connection to, the company in order to continue pursuing their clinical work at Johns Hopkins University.
Commercial ingredients were not used in this study.
- How long did it take for you to see improvement in the study subjects?
This was a single, small study which needs to be replicated. In the limited number of individuals in this study, behavioral differences were observed quite early and they persisted throughout the 18-week trial. Once subjects stopped taking broccoli sprout extract, their behavioral measurements tended to return to their pre-intervention state. In addition, since ASD is probably a range of conditions rather than a single disorder, it is not surprising that there was a range of degrees of improvement (and of return to pre-existing status).