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Researchers have proposed numerous possible reasons to explain the increase in obesity rates, one of which is that average portion sizes have been steadily increasing over the past several decades. These analyses are typically based on calories acquired from sources outside the home (e.g., at restaurants or via ready-made products or drinks). Does the same pattern occur for foods prepared at home? In other words, is the average home-cooked recipe more caloric today than its counterpart from several decades ago?
In 2009, Brian Wansink (a leading food psychologist and whose work on Chinese buffets I've previously covered here) along with Collin R. Payne published a letter (very short paper) in the Annals of Internal Medicine where they investigated this issue using a highly creative source of data. They conducted a caloric analysis of 18 recipes that had been continuously covered in seven editions of the classic cookbook The Joy of Cooking (1936, 1946, 1951, 1963, 1975, 1997, and 2006). Here are the key findings as reported in their Table (only the means are reported here, beginning with the year 1936 and ending in 2006):
Mean total calories per recipe (statistically higher in 2006 as compared to 1936):
2123.8 2122.3 2089.9 2250.0 2234.2 2249.6 3051.9
Mean average calories per serving (statistically higher in 2006 as compared to 1936):
268.1 271.1 280.9 294.7 285.6 288.6 384.4
Mean number of servings per recipe (statistically the same in 2006 as compared to 1936):
12.9 12.9 13.0 12.7 12.4 12.4 12.7
Bottom line: The average increase in mean total calories per recipe was 43.70% in comparing 1936 to 2006. This is quite an extraordinary increase (928.1 calories) largely driven by the use of more caloric ingredients.
Some of my own calculations as food for thought: Assuming that one such recipe was eaten per week for a full year both in 1936 and 2006. This would amount to the following additional calories per year in 2006: 928.1 calories x 52 weeks = 48,261.2 calories per year. If we divide this by 3,500 calories (the amount of calories that correspond to one pound of fat), we get a weight gain of: 13.79 pounds per year!
Source for Image:
http://www.rabelaisbooks.com/pictures/1554.jpg
