Truffles are a genotsmiddel (luxury food supplement).
The truffle can be freely produced, traded and exported in the Netherlands. It can also be freely given to third parties in therapeutic sessions.
It is a legal product in the Netherlands, as long as it has not undergone “active processing”.
No medical claims can be made because no science exists to corroborate it.
If you as a therapist or guide, provide the truffles to the client, the law sees you as a “tour operator” and holds you responsible for the consequences. For this reason the client should either purchase them or they should be “sponsored” and accepted by the client.
Regardless of its legal status, financial institutions tend to shun away and not accept businesses that work (legally) with truffles or any guiding associated with it.