The USDA's first nutrition guidelines were published in 1894 by Dr. Wilbur Olin Atwater as a farmers' bulletin.
In Atwater's 1904 publication titled Principles of Nutrition and Nutritive Value of Food, he advocated variety, proportionality and moderation; measuring calories; and an efficient, affordable diet that focused on nutrient-rich foods and less fat, sugar and starch. This information preceded the discovery of individual vitamins beginning in 1910.
A new guide in 1916, Food for Young Children by nutritionist Caroline Hunt, categorized foods into milk and meat; cereals; vegetables and fruits; fats and fatty foods; and sugars and sugary foods.
How to Select Food in 1917 promoted these five food groups to adults, and the guidelines remained in place through the 1920s.
In 1933, the USDA introduced food plans at four different cost levels in response to the Great Depression.
In 1941, the first Recommended Dietary Allowances were created, listing specific intakes for calories, protein, iron, calcium, and vitamins.