Their [plant secondary compounds] healthful effects....

“ Their [plant secondary compounds] healthful effects in humans, however, are not well understood, in part because things in nature like coriander and basil can't be patented so there isn't a lot of money being thrown at them, and in part because long-term studies that measure small effects of low doses are expensive and don't yield the kind of unambiguous, major effects you get with pharmaceuticals, but mainly because preventions are never as exciting as cures. ”

Mark Schatzker

From : The Dorito Effect: The Surprising New Truth About Food and Flavor