“Life is like a sandwich—the more you add to it, the better it becomes” is a saying that has been printed on many images. “Life is like a sandwich: the more you add to it the better it becomes” was printed in The Jackson County Banner (Brownstown, IN) on October 22, 1991. Authorship is unknown.
       
“Life is like a sandwich—you have to fill it with the best ingredients” is a similar saying.
 
     
22 October 1991, The Jackson County Banner (Brownstown, IN), “Mt. Zion” by Mrs. Inez Baughman, pg. 15, col. 2:
Life is like a sandwich: the more you add to it the better it becomes.
   
25 February 1992, Titusville (PA) Herald, “Tryonville” by Myrtlette Sterner, pg. 10, col. 1:
Thought for the week: Life is like a sandwich. The more you add to it the better it becomes.
 
Google Groups: rec.motorcycles 
What’s the fastest you ever got clocked at? 
Steve B. Hill
9/21/93
(...)
Life is like a sandwich, the more you put in, the better it tastes
       
Google Books
1001 Things Your Mother Told You: (And You Should Have Listened To!)
Quotes, Sayings, and Timeless Wisdom
By Croft M. Pentz
Wheaton, IL: Tyndale House Publishers
2001
Pg. 168:
Life is like a sandwich — the more you add to it, the better it becomes.
 
Google Groups: argonet.acorn.voyager
Connection and Authentication
Gordon Stevenson
7/21/01
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Life is like a sandwich. The more you add to it, the better it becomes!
   
Twitter
Michelle Williams
@Awinnah
Life is like a sandwich - the more you add to it the better it becomes
7:51 PM - 15 Apr 2009
 
1 June 2011, Sarasota (FL) Herald Tribune, “Try a mouthful of muffaletta” by Linda Brandt, pg. E2:
I found a quote that most certainly applies to muffalettas. “Life is like a sandwich—the more you add to it, the better it becomes.”
   
23 May 2014, Daily News (New York, NY), “Submarine Warfare: Slice of life doesn’t cut mustard” by Joe Oziemianowicz, pg. 48:
A sign hangs on the wall in Dane Laffrey’s set, which is true to life -except there are no prices next to -sandwich options. It reads: “Life is like a sandwich - the more you add to it, the better it becomes.”
       
USA Today—ForTheWin
A group of kids came up with sandwiches that sound worse than Dale Earnhardt Jr.‘s favorite
By: Michelle R. Martinelli | April 6, 2017 2:55 pm
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JR Motorsports
@JRMotorsports
Life is like a sandwich - the more you add to it, the better it becomes! #JRM360 #StrangewichChallenge More info: http://bit.ly/2o23Axa
1:04 PM - Apr 6, 2017
 
Fayetteville (NC) Observer
Flip Flop Sandwich Shop has a ‘build your own’ concept
By ALison Minard
Posted Aug 10, 2017 at 11:00 AM
Updated Aug 14, 2017 at 2:52 PM
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A sign in front of the counter reads, “Life is like a sandwich. The more you add to it the better it gets.”
 
Twitter
Lynne Bryce
@Optio_VA
This week is #BritishSandwichWeek 🥪
‘Life is like a sandwich - the more you add to it, the better it becomes.’
#lifequotes #quote #TuesdayThoughts #EarlyBiz #innovation #inspiration #Motivation #love #life #happiness #sandwich
2:28 AM - 22 May 2018