“A diplomat’s life is made up of three ingredients: protocol, Geritol and alcohol” was a popular saying of at least two statesmen in the 1950s and 1960s. (Geritol is a trademarked multivitamin dietary supplement that was first sold in 1950.) Howard Beale (1898-1983), the Australian Ambassador to the United States, in 1959 described diplomatic life in Washington as a mixture of “protocol, alcohol and Geritol.”
 
The saying is most associated with Adlai Stevenson II (1900-1965), who served as U.S. Ambassador to the United Nations from 1961 until his death in 1965. The syndicated columnist Walter Winchell quoted Stevenson in September 1964:
 
“This is the social life of a diplomat: Protocol, Alcohol and Geritol.”
 
   
Wikipedia: Howard Beale (politician)
Sir Oliver Howard Beale KBE (10 December 1898 – 17 October 1983) was an Australian politician and Ambassador to the United States. He was the father of Liberal Party of Australia politician Julian Beale. Beales’s granddaughter, Debbie Beale, was married to Labor party politician Bill Shorten.
   
Wikipedia: Adlai Stevenson
Adlai Ewing Stevenson II (5 February 1900 – 14 July 1965) was an American politician and statesman, noted for his skill in debate and oratory; Governor of Illinois, he was twice an unsuccessful candidate for President of the United States running against Dwight D. Eisenhower (in 1952 and 1956). Under the John F. Kennedy administration, he served as United States Ambassador to the United Nations.
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A diplomat’s life is made up of three ingredients: protocol, Geritol and alcohol.
. As quoted in The New York Times Magazine (7 February 1965).
 
26 April 1959, Dallas (TX) Morning News, ‘Washington” by Walter C. Hornaday, sec. 1, pg. 16, col. 3:
Australian Ambassador Howard Beale made a hit last week when he addressed the weekly Texas congressional delegation luncheon. His views particularly pleased Speaker Sam Rayburn. The Ambassador proudly called himself a politician and said he had found diplomats without political experience didn’t do the best job. Beale jokingly described diplomatic life in Washington as a mixture of “protocol, alcohol and Geritol.”

17 January 1961, The Valley News and Valley Green Sheet, (Van Nuys, CA), pg. 1, col. 1:
THEY RHYME
“Protocol, alcohol and Geritol.”
—FRANCIS O’CONNELL
about Washington, D.C. society
 
20 July 1964, Morning Advocate (Baton Rouge, (LA), “The Lyons Den” by Leonard Lyons, pg. 2-A, col. 2:
Adlai Stevenson, as chairman of the Eleanor Roosevelt Foundation, spoke in Poughkeepsie last week. He said that the social life of a U.N. diplomat can be defined in three words: “Protocol, alcohol, Geritol.”
 
4 August 1964, San Diego (CA) Union, “Walter Winchell’s America,” pg. A6, col. 6:
U.N. Ambassador Adlai’s quippersnapper: “This is the social life of a diplomat: Protocol, Alcohol and Geritol.”
 
8 September 1964, Reno (NV) Evening Gazette, “Words, Wit and Wisdom” by William Morris, pg. 4, col. 6:
In this connection, let’s pass on the latest Adlai Stevenson witticism. The life of a diplomat, he reports, is compounded of three elements, “Protocol, alcohol and Geritol.”
 
13 September 1964, Daily Tribune (Great Bend, KS),  “Vaughan at Large: Prof. Adlai explains strange tribal rite,” pg. 4, col. 3:
He acknowledged the professional interest of the pupils by saying, “When I was in active politics I envied the serenity of diplomatic life. Now that I am in diplomacy I often envy the serenity of politics.”
 
“I once said that diplomacy was composed of protocol, alcohol and Geritol. A political convention is handshakes, headaches and heartbreaks.”
 
Google Books
23 July 1965, Life magazine, pg. 27, col. 3:
(From a collection of Adlai Stevenson quotes recalled at his death—ed.)
The social life of a U.N. diplomat can be defined in three words — protocol, alcohol and Geritol.
POUGHKEEPSIE, JULY 1964
   
Google Books
Dick Enberg’s Humorous Quotes for All Occasions:
Speaking Tips and Over 1,000 One-Liners
By Dick Enberg with Brian and Wendy Morgan
Kansas City, MO: Andrews McMeel
2000
Pg. 169:
The prerequisites for being in the diplomatic corps are the ability to handle protocol, alcohol, and Geritol.
Wallace Rowling (New Zealand’s Ambassador to the United States, 1985-88—ed.)