Updated: Dec 4, 2021
You may have heard of the The U.S. Department of Agriculture’s Food Pyramid, and most recently MyPlate. And while guidance about nutrition has been provided as a government service since 1916 (see a "Brief History Of" attachment) it's been frequently influenced by food industry lobbyists.
The Healthy Eating Plate, created by experts at Harvard School of Public Health and Harvard Medical School, points consumers to the healthiest choices in the major food groups. It is based exclusively on the best available science and was not subjected to political or commercial pressures from food industry lobbyists.
As you see above, it's very clear that a variety of foods with an abundance of fruits and vegetables is the recommendation. With each meal, yes breakfast/lunch/dinner - aim to create a meal that resembles the Healthy Eating Plate. Serving sizes are approximately your palm size.
Check out the Harvard Medical School's Healthy Eating Plate Questions and Answers for more fantastic information and details!
"Let food by thy Medicine!" ~ Hippocrates