Source: http://www.1920-30.com/food/condiments.html
QUOTE
Use of this sort of condiments must, therefore, be very moderate. Those who get the habit of using them quickly become its slaves, and find all foods tasteless that have not been drenched with pepper and mustard. They are laying the ground, for dyspepsia, which will compel them to give up such injurious practises—perhaps even for some ulcer of the stomach or duodenum, whose consequences can not be foreseen. In any case, they bring on premature fatigue of the liver, leading to the hepatic complaints now so common and so difficult to cure.
Goddamn, apparently ANYONE could be a doctor back in the 20s, and just say whatever the hell they wanted to!
I'll bet that viral hepatitis hadn't been discovered yet at that point in time.