“Let food be thy/your medicine and medicine be thy/your food” is often cited as a famous saying of Hippocrates (460 B.C.-370 B.C.). However, it’s not known what ancient writing is most closely related to this saying.
 
“Let food be your medicine” was cited in English print in July 1913. “Let your FOOD be your medicine and your medicine be your FOOD” was cited in an 1939 advertisement for a health food store. “Think about Hippocrates’ advice, ‘Let food be your medicine, and medicine be your food’” was cited in 1967.
 
   
Wikipedia: Hippocrates
Hippocrates of Cos or Hippokrates of Kos (Greek: Ἱπποκράτης; Hippokrátēs; c. 460 BC – c. 370 BC) was an ancient Greek physician of the Age of Pericles (Classical Greece), and is considered one of the most outstanding figures in the history of medicine. He is referred to as the father of western medicine in recognition of his lasting contributions to the field as the founder of the Hippocratic School of Medicine. This intellectual school revolutionized medicine in ancient Greece, establishing it as a discipline distinct from other fields that it had traditionally been associated with (notably theurgy and philosophy), thus establishing medicine as a profession.
 
However, the achievements of the writers of the Corpus, the practitioners of Hippocratic medicine, and the actions of Hippocrates himself are often commingled; thus very little is known about what Hippocrates actually thought, wrote, and did. Hippocrates is commonly portrayed as the paragon of the ancient physician, credited with coining the Hippocratic Oath, still relevant and in use today. He is also credited with greatly advancing the systematic study of clinical medicine, summing up the medical knowledge of previous schools, and prescribing practices for physicians through the Hippocratic Corpus and other works.
   
22 July 1913, Kansas City (MO) Star, pg. 14, col. 2:
LET FOOD BE YOUR MEDICINE.
Many Fruits and Vegetables Are Good for Common Ailments.
 
Google Books
The Key to Rational Dietetics
By Otto Carqué
Los Angeles, CAL, Carqué Pure Food Co.
1926
Pg. 3:
“Let your food be your medicine”
 
Hathi Trust Digital Library
Health Through Sunshine and Diet
Second Edition
By Gustave W. Haas.
Long Beach, CA: Health Laboratories
1926
Pg. 161:
LET FOOD BE YOUR MEDICINE
(Bower’s Health Food Remedies—ed.)
 
25 April 1928, Riverside (CA) Daily Press, pg. 6, col. 7 ad:
Let Food Be Your Medicine
(The Health Food Store—ed.)
 
27 March 1939, Canton (OH) Repository, pg. 11, col. 2 ad:
Let your FOOD be your medicine and your medicine be your FOOD.
(Schauer’s Health Food Centre—ed.)
 
1 April 1967, Rockford (IL) Register-Republic, “On Additives to Food” (letter), pg. A6, col. 2:
Think about Hippocrates’ advice, “Let food be your medicine, and medicine be your food.”
(Letter by Helen Vanderlinde, Rochelle, IL—ed.)
 
Google News Archive
17 August 1977, The Daily Union Democrat (Sonora, CA), pg. 6, col. 7 ad:
“LET FOOD BE YOUR MEDICINE”
(Naturally Good foodstore & herbs—ed.)
 
Google Books
Ann Wigmore’s Recipes for Longer Life
By Ann Wigmore
Wayne, NJ: Avery Pub. Group
1978
Pg. 192 (back cover):
Much of her philosophy is as old as Hippocrates himself who taught that if given the correct nourishment, the body will heal itself, and advised, Let food be your medicine.
 
OCLC WorldCat record
Let food be thy medicine : 185 scientific studies showing the physical, mental, and environmental benefits of whole foods
Author: Alex Jack
Publisher: Becket, Mass. : One Peaceful World Press, 1991.
Edition/Format:   Book : English : 1st ed
 
Google Books
God’s Health Plan—The Audacious Journey to a Better Life
By Ricki Pepin
Maitland, FL: Xulon Press
2007
Pg. 235:
“Let food be your medicine…”
Hippocrates
Most people are familiar with the above quote from Hippocrates, but it is only a partial quote. His statement preceding this famous quote illustrates that he understood the principles of how God designed our bodies, and the relationship between food and health, even if he didn’t know about free radicals and antioxidants.
 
“Natural forces within us are the true healers. Let your food be your medicine. let your medicine be your food.”
—Hippocrates
 
Food Republic
Word Of The Day: Macrobiotic
Mar 29, 2012 12:31 pm
There is an old saying, “let food be your medicine and medicine be your food.” In other words, eating a well-balanced diet containing all the nutrients you need is beneficial. Deep, huh? Let it marinate in your brain for a moment because it gets better.