How many calories a person needs to eat each day for optimum health depends on many factors, such as sex, height, age and genetics. Researchers can find the average calories that a population eats through surveys and calculating the calories per capita.
USDA: Calories Per Capita
Calories per capita indicates the amount of food consumed per person. The average daily per capita calorie consumption for the U.S. in 2010 was 2,534, according to a report from the University of Michigan.
Average Adult Consumption
The National Health and Nutrition Examination Survey done for the years 2005 to 2006 concluded that the average American adult male, age 20 years and older, consumes 2,638 calories daily, and the average adult female of that age group consumes 1,785 calories.
According to the same study, 2- to 5-year-old males consume an average of 1,641 calories, while females of the same age group consume 1,486 calories. Six- to 11-year-old males consume 2,092 calories on average daily, while females consume 1,879 calories. Twelve- to 19-year-old males eat 2,707 calories on average, and females take in 1,906 calories daily.