A popular one-panel comic strip (cited in print since at least April 2009) by “BRIAN” has this dialogue:
 
BUNNY: Don’t forget. You are what you eat.
BEAR: I need to eat a skinny person.”
 
“If you are what you eat then I need to eat a skinny person!” was cited on Twitter on March 6, 2009.
 
Jean Anthelme Brillat-Savarin (1755-1826), in the book Physiologie du Gout (1825), wrote “Tell me what you eat, and I shall tell you what you are,” often interpreted as “you are what you eat.” This was figurative and not meant literally; one does not become an apple or a donut or a “skinny person” by eating such things.
 
 
Wikiquote: Food
Dis-moi ce que tu manges, je te dirai ce que tu es. Tell me what you eat, and I shall tell you what you are.
. Jean Anthelme Brillat-Savarin, Physiologie du Gout (1825); tr. M. F. K. Fisher, The Physiology of Taste: Or Meditations on Transcendental Gastronomy (1949)
. Variants:
..Der Mensch ist, was er ißt. Man is what he eats.
..Ludwig Andreas Feuerbach, Die Naturwißensschaft und die Revolution [Natural science and the revolution] (1850), repeated in Das Geheimnis des Opfers, ober der Mensch ist was er ißt [The mystery of sacrifice, or man is what he eats] (1862)
..You are what you eat.
..Victor Lindlahr, You Are What You Eat: how to win and keep health with diet (1942)
 
Twitter
Redd Hynes
‏@DameNamedRedd
If you are what you eat then I need to eat a skinny person!
8:07 PM - 6 Mar 2009
 
Twitter
acorndreaming
‏@acorndreaming
Words of wisdom from my mother. “They say that you are what you eat.  In that case, I need to eat a skinny person.  That is my diet plan”
4:47 PM - 2 Apr 2009
 
Diane’s Addled Ramblings
Friday, April 3, 2009
Friday Funnies…
As I head out the door to meet a friend… a skinny friend… for Mexican food, I leave you with this…
{"Bunny: Don't forget. You are what you eat. Bear: I need to eat a skinny person." -- ed.)

Calorie Count
sauvignon
May 18 2009 01:29
I saw this one somewhere recently, forgot where, and it’s weight loss related!
 
A bunny is talking to a sad-looking bear. The bunny: Remember, you are what you eat! The bear: I need to eat a skinny person.
 
Made me smile.
 
Facebook
“You are what you eat.” “I need to eat a skinny person…”
(Joined Facebook February 18, 2010—ed.)
 
Food and Society
Friday, May 4, 2012
“I need to eat a skinny person”
I’ve always heard the saying “you are what you eat” but never quite grasped the complexity and truthfulness of such a statement. I like to believe that I am not anything like the cow or chicken I just consumed for lunch. However, after talking about cultural and emotional connections we have to the foods we eat, the saying is starting to make a whole lot more sense.
 
someecards
05.27.2012
If you are what you eat, then I need to eat a skinny person.
 
someecards
10.27.2012
If you are what you eat, I need to eat a skinny person…