The finding suggests that the phenomenon of serving bigger portions on bigger plates – which pushes people to overeat – has occurred gradually over the millennium.
"We took the 52 most famous paintings of the Last Supper (from the book 'Last Supper,' 2000) and analyzed the size of the entrees, bread and plates, relative to the average size of the average head in the painting," said Brian Wansink, the John S. Dyson Professor of Marketing and of Applied Economics and director of the Cornell Food and Brand Lab.
The study found that the size of the entrées in paintings of the Last Supper, which according to the New Testament occurred during a Passover evening, has progressively grown 69 percent; plate size has increased 66 percent and bread size by about 23 percent, over the past 1,000 years.
The analysis was aided by computer-aided design technology that allowed items in the paintings to be scanned, rotated and calculated regardless of their orientation in the painting.
The researchers started with the assumption that the average width of the bread is twice the width of the average disciple's head.
"The last thousand years have witnessed dramatic increases in the production, availability, safety, abundance and affordability of food," said Wansink. "We think that as art imitates life, these changes have been reflected in paintings of history's most famous dinner."
Citation: Brian Wansink, Craig Wansink, 'The Largest Last Supper', International Journal of Obesity, April 2010