Rules for the many powers of.... food?

[Pursuivant]

There's an early 20th century short story by Saki called "Filboid Studge" which features a sort of bland, soulless, hard-to-eat breakfast cereal which upright, middle class English people grimly consume because they believe it improves their health moral character.

In GURPS terms, it might give +1 Will but also Dull, Staid, and quirk level OPH (Self-Righteousness), Sense of Duty (Nation) and No Sense of Humor.

Lots of foods and drinks which were controversial in their day might have similar effects, as long as net character point costs all worked out to zero.