“Breakfast is the most important meal of the day” is a common saying. Breakfast is the first meal of the day, providing fuel for the day’s activities. The saying appears to have been popular since the 1880s, although earlier citations can be found. With the rise of public schooling (by the 1880s), parents were told how important a good breakfast is to their children’s performance at school.
   
The saying appears—not surprisingly—in breakfast food advertisements. In 1901, Grape-Nuts advertised it in national newspapers: “The breakfast is perhaps the most important meal of the day.” In 1922, a Shredded Wheat advertisement read: “Breakfast is the most important meal of the day.”
 
Variations of the saying include “Breakfast tacos are the most important meal of the day,” “Coffee: The most important meal of the day” and “Pizza is the most important meal of the day.”
   
 
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The Lollards:
A Tale
By Thomas Gaspey
Volume I
London: Longman, Hurst, Rees, Orme, and Brown
1822
Pg. 122:
By this time breakfast was over, and Whittington, engaged as he had been in conversation, was surprised to find that notwithstanding it was nearly seven o’clock, he was still seated at the table. He now gave directions to have the next and most important meal of the day ready between ten and eleven, remarking by the way, “when four hours be past after breakfast, then a man may safely taste his dinner.”
     
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A Treatise on Diet and Regimen
By William Henry Robertson, M.D.
Fourth Edition
Volume I
London: John Churchill
1847
Pg. 285: 
The breakfast should always be an important, if not the most important, meal of the day.
   
17 April 1880, Chester (PA) Daily Times, pg. 1, col. 5:
it is noticeable that in our largest cities business men are fast adopting the English custom of light luncheons at noon, the more important meal of the day being reserved for a later hour.
     
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Domestic economy
By E. Rice
Published by , 1884
Pg. 140:
BREAKFAST DISHES. Breakfast is perhaps the most important meal of the day, though in these times of rush and hurry it does not always receive the attention it deserves.
   
2 April 1885, Calliope (Iowa) Independent, “Health and Food for School Girls,” pg. 6, col. 3:
The breakfast of school-girls is the most important meal of the day; not only have they to replace in the blood the nutritive elements which have been assimilated during the night to meet the demands of growth and development, but they must provide for the activity of mind and body which their daily tasks impose upon them.
(From Harper’s Bazaar—ed.)
 
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January 1886, The Bookmart, pg. 227, col. 1:
To men breakfast is really the most important meal of the day, and is usually the one that is most neglected or scamped. 
 
6 April 1887, Titusville (PA) Herald, ‘Eat Before You Drink,” pg. 2, col. 2:
“A large proportion of intemperance in the use of stimulants,” philosophized a physician, “may be laid to the light breakfast eaten by most people. Breakfast is the most important meal of the day and sufficient importance is not attached to it in the majority of households.”
 
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Common Sense Health Notes
By A. R. Horne, D. D. (Abraham Reeser Horne—ed.)
Chicago, IL: A. Flanagan, Publishers
1893
Pg. 114:
The morning meal, or breakfast, breaking the fast, Frueh-Stueck, early piece, “early bit,” is the most (Pg. 115—ed.) important meal of the day. On it, and the time it is taken depend, to a great extent, our feelings of the day. It should be taken within an hour after leaving the bed, and especially before going out into the raw air and dampness of the morning. If the “fast is not broken” soon, the physical and mental energies, unsupported by food, gradually lessen and exhaustion ensues.
   
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The True Science of Living:
The New Gospel of Health
By Edward Hooker Dewey, M.D.
Norwich, CT: The Henry Bill Publishing COmpany
1895
Pg. 148:
I resolved to chance a foreign breakfast, but I was not hungry, and should I take the roll? “Oh, you must,” says habit; says custom. “It is the most important meal of the day after so many hours of fasting, so you must always eat whether hungry or not.”
       
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The Breakfast Plan and the Fasting-Cure
by Edward Hooker Dewey, M.D.
ville, PA: Published by the Author
1900
Pg. 64:
Now the American breakfast, in point of sheer necessity, is believed to be the most important meal of the day, as the means for strength that is to be called out for the forenoon of labor, and believed with a force of insistance that waarrants a conclusion that a night of (Pg. 65—ed.) sleep is more exhausting to all the powers than the day of labor.
 
29 June 1901, Atlanta (GA) Constitution, “Good Breakfasts; Start the Day Right,” pg. 7 ad:
The breakfast is perhaps the most important meal of the day. Europeans usually eat a very light brenkfast. Many American have stomach trouble because they eat too much or food of not the right sort for the morning meal. An ideal breakfast is a baked apple or some other fruit, a dish of Grape-Nuts Food with a little cream, and a cup of Postum Food Coffee.
 
2 May 1909, Los Angeles (CA) Times, “Mastication and Digestion,” pg VII6:
DINNER, the most important meal of the day, is attended with a certain degree of ceremony in the most modest household.
     
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February 1916, The Medical Summary (Philadelphia, PA), pg. 384:
Breakfast should be the best and most important meal of the day. There is no better evidence of health than a good appetite upon arising.— A. H. Doty, Public Health.
   
13 February 1916, Chicago (IL) Daily Tribune, “Fruits and Their Uses—Breakfast Dishes” by Phoebe Burbank, pg. 647?:
BREAKFAST is, in many households, the most important meal of the day.
   
29 April 1919, Kansas City (MO) Star, pg. 9 ad:
Start the Day Right
Breakfast is the most important meal of the day.
(Warneke’s Butter Bread—ed.)
 
20 March 1921, Lexington (KY) Herald, section 2, pg. 12 ad:
Breakfast
Your Most Important Meal Of The Day
(March’s store—ed.)
 
23 October 1921, Duluth (MN) News-Tribune, “Home Bureau Forms Classes in Nutrition,” pg. 4:
The efficiency of school children is dependent upon a diet, and the most important meal of the day is breakfast.
 
27 February 1922, Trenton (NJ) Evening Times, pg. 11 ad:
Better Breakfasts Build Better Bodies
Breakfast is the most important meal of the day. You can eat “any old thing” at night and “sleep it off”—but breakfast fills the day with sunshine or sadness.
(Shredded Wheat—ed.)
 
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Constructive Hygiene
By Frederic Albert Woll, American Optometric Association
Published by s.n., 1926
“Address delivered at Educational Congress, 29th annual convention, American Optometric Association, San Francisco, California, June 1926”
It should be obvious that breakfast is the most important meal of the day. 
     
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Caravanning and Camping:
A Complete Guide to Camping and Motoring with Caravan Or Tent
By Archibald Henry Montgomery Ward
Published by Sir I. Pitman & Sons, Ltd., 1931
Pg. 130:
Generally, in camp, supper is the most important meal of the day,
   
28 May 1943, Chicago (IL) Tribune, “Eat a Hearty Breakfast to Build Health!” by Mary Meade, pg. 18:
“Breakfast is the most Important meal of the day to me, and If I don’t eat well in the morning I feel terrible all day.”
   
29 August 1947, Los Angeles (CA) Times, “Use Cereals in Breakfasts All Summer” by Marian Manners, pg. A6:
From many standpoints breakfast is the most Important meal of the day.
   
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15 July 1948, St. Petersburg (FL) Evening Independent, pg. 2, col. 7 ad:
So give a better break to breakfast in your home. Nutritionists say it’s the most important meal of the day.
   
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18 September 1953, St. Petersburg (FL) Times, “Morning Meal Most Important, Say Dieticians,” pg. 37, col. 1:
Breakfast is the most important meal of the day. even for dieters, for fruit juice, cereal with an egg and bacon, toast and coffee will add fewer pounds in the long run than a breakfast of only coffee with sweet rolls.
 
10 September 1954, Los Angeles (CA) Times, “Get Family Off to Good Start at Breakfast” by Marian Manners, pg. B4:
Medical advice tells us that it Is the most important meal of the day.
   
8 November 1959, Los Angeles (CA) Times, “Weight Woes Switch Sides” by Mary Lou Loper, part IV, pg. D1:
“Breakfast is the most important meal of the day.”
     
14 September 1972, Washington (DC) Post, pg. D1:
Breakfast: The Most Important Meal of the Day
Breakfast Suggestions to Start the Day
By Edith Vanocur
 
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Breakfast: Most Important Meal of the Day
By Christine Dean and Tim Lewis
Published by Meridian Education Corporation
2003