Brian Wansink, a marketing professor at Cornell University, and co-author Collin Payne of New Mexico State University-Las Cruces examined 18 recipes -- ranging from beef stroganoff to apple pie -- that have been continuously published in the classic cookbook since 1936. They found the average number of calories per recipe in 1936 was about 268 calories per serving. In 2006, the average number of calories per recipe was about 436 calories a serving, the Cornell Chronicle reported.
Wansink, who previously was executive director of the U.S. Department of Agriculture's Center for Nutrition Policy and Promotion, said the increase in calories was influenced by increases in fat and sugar and changes in serving size.
"What served four people in 1986 would have served almost seven people by 1936 standards," Wansink said.