“Chocolate makes my/your clothes shrink” (or “Avoid chocolate—it makes clothes shrink”) is a jocular saying that has been printed on many gift items, such as posters and T-shirts. “I still think all those chocolate covered cherries just made my clothes shrink” was cited in print in 1992, but the saying has been popular on the Internet since about 2003.
 
“Chocolate makes my/your clothes shrink” gift items are often sold with Valentine’s Day chocolates.
 
   
Google News Archive
9 January 1992, Harlan (KY) Daily Enterprise, “Certain foods spark memories of the good ole days” by Phyllis Sizemore, pg. 4, col. 3:
But through it all, I can’t really believe that I’ve gained weight. I still think all those chocolate covered cherries just made my clothes shrink.
 
16 July 1998, Toronto (Ontario) Star, “Daly gets it all out in open,” Sports, pg. 1: ‎
JOHN DALY has discovered, albeit the hard way, that nasty truth about chocolate making your clothes shrink.
   
Google Goups: alt.fan.john-denver
Dr Pepper
5/20/99
(...)
Peggy-I don’t think storing clothes in the closet together with the chocolate makes them shrink…...I think it is digesting the chocolates and metabolizing them that makes those clothes shrink…..Ha,ha…..Maybe that is why I subconsciously buy everything way too big…...so funny…..Lorraine
     
Leyland Forum
Star Sailor Cat
Posted - 24 Apr 2003 :  16:27:27
(...)
Chocolate makes clothes shrink
 
The End of the World
Sunshine makes vitamin D and that makes you un-sad!
Jan. 23rd, 2006 at 8:56 PM
I walked past a Valentine’s window display at a store that featured a pink pillow reading, “Chocolate makes my clothes shrink!” It says something about me that I laughed, not immediatly thinking, “Chocolate makes me fat!” but “Will dress like ho for food!”
 
Google Books
Shubnell’s Profound Thoughts, Book 3
By Thomas F. Shubnell
Published by author
2009
Pg. 24:
Chocolate makes my clothes shrink.
 
Google Books
Sustainable Weight Loss:
The Definitive Guide to Maintaining a Healthy Body
By D. Lee Waller
Bloomington, IN: iUniverse
2011
Pg. 265:
The secret lies in eating the right foods and eating them in the right quantities. Scientists have shown that chocolate doesn’t make your clothes shrink.
 
cafemom
Not all chocolate makes your clothes shrink, some shrink your wallet.
Posted by itsallabtthem84 on Apr. 29, 2012 at 7:23 PM
I found out what I am getting for my birthday and it’s chocolate but it won’t shrink my clothes, lol. It will be here around the 12th since my husband shops last mintue for everything. He forgot to clean out his pockets as usual and that is how I found out.