Sulforaphane can not be absorbed to a great extend only through the consumption of broccoli
Even those who eat plenty of broccoli will be disappointed on the basis of fact that broccoli nowadays, does not provide the body with to many nutrients. This is based on the newer cultures of broccoli that do not contain a lot of glucoraphin. Often, the valuable ingredients in broccoli are destroyed by storage, by deep freezing and by cooking. The reason for that the enzyme myrosinase, which is very sensitive. It converts glucoraphanin into the active ingredient sulforaphane. It can already be destroyed by cooking broccoli at 40 degrees celsius. For this reason, broccoli would have to be eaten raw in order to absorb a large amount of the valuable ingredients. Quercetin is also reduced by storage and in production processes. Therefore, cooking also destroys most of the quercetin.