“What’s the difference between a vitamin and a hormone?” (joke)

A popular joke about vitamins is:
 
Q: What’s the difference between a vitamin and a hormone?
A: You can’t hear a vitamin.

 
That is, you can hear a “hormone” (“whore moan”). The punchline varies and is sometimes given as, “You can’t make a vitamin.”
 
The “hormone”/“whore moan” pun has been cited in print since at least the 1950s.
   
   
Google Books
The Virginia Spectator
1954
Pg. 91:
He: “What’s the difference between a vitamin and a hormone?”
She: “Dunno.”
He: “I never heard a vitamin!”
 
Google Books
Intro 6:
All of us and none of you and other original fiction and poetry with a symposium on book reviews in America

Edited by George Garrett
Garden City, NY: Anchor Books
1974
Pg. 87:
You know the difference between a vitamin and a hormone? You can’t hear a vitamin.
 
Google Books
Dirty Stories for All Occasions
By Andrew L. Cleveland
New York, NY: Galahad Books
1980
Pg. 12:
What’s the difference between a vitamin and a hormone?
You can’t hear a vitamin.
 
Google Books
The Public Speaker’s Joke Book
By Kevin Goldstein-Jackson
Tadworth, SUrrey: Elliot Right Way Books
1991
Pg. 116:
The difference between a vitamin and a hormone is that you cannot hear a vitamin.
 
Google Books
Blanche Knott’s Treasury of Tastelessness
By Blanche Knott
New York, NY: St. Martin’s Press
1994
Pg. 90:
What’s the difference between a hormone and an enzyme?
You can’t hear an enzyme.
 
reddit
What’s the difference between a vitamin and a hormone?
submitted October 19, 2012 by Tyguy732
You can’t make a vita-min. But you can make a hor-mone!
 
YouTube
what’s the difference between a vitamin and a hormone
jellybeartv
Published on Feb 1, 2013
joke what’s the difference between a vitamin and a hormone
   
Google Books
Buying the Programme
Book One of the Small Wars Trilogy

By Alan Watkins-Groves
Lulu Press, Inc. (Lulu.com)
2014
Pg. ?:
I remembered an old joke. ‘What’s the difference between a vitamin and a hormone? You can make a vitamin but you can’t make a whore moan.’
 
reddit
What’s the difference between a vitamin and a hormone?
submitted May 7, 2015 by The_Intensity
I’ve never made a vitamin…
 
reddit
What’s the difference between a vitamin and a hormone?
submitted September 13, 2016 by baiti
You can’t make a vitamin.