The "freshman 15" - the rapid weight gain believed to afflict many new college students when they begin school - appears to be a bit of an urban legend: a cautionary tale often told but not well substantiated.
Now a study of 36 freshmen at Auburn University - located in one of the states with the highest prevalence of obesity in the nation - reports an average gain of only 1.9 pounds during the first semester, with women gaining slightly more than men, and an average gain of only 4.8 pounds for the entire freshman year (with males gaining an average of 5.4 pounds and women gaining an average of 3.2 pounds). Some students lost weight. But even when only those who gained were considered, the average weight gain was 5.8 pounds, a long way from the often-popularized 15.
Dr. Sareen Gropper presented the study at the Experimental Biology 2008 meeting in San Diego on Sunday, April 6. The presentation is part of the scientific program of the American Society for Nutrition.
The 36 freshman (26 females and 10 males) were weighed and their body composition and shape measured when they began college and then again at the end of the fall semester and the end of the spring semester. The urban legend is correct in the sense that a majority of freshmen in the study (71.4 percent) did gain weight, notes Dr. Gropper, but only 21 percent gained five pounds or more. The largest gainers in the fall semester were a woman who gained nine pounds and a male who gained 10 pounds. For the academic year, the largest weight gains observed were 13 pounds for one male and 12 pounds for one female. No one gained the freshman 15.
Dr. Gropper and colleagues have begun a larger study of 240 students who entered Auburn in the fall semester of 2007. Like the pilot study, participants had to be between 17 and 19 years of age, not married, having no children, and without diagnosed eating disorders. At the end of the first semester, 68.7 percent of students had gained weight: an average of 2.1 pounds. Only 21 percent of students gained 5 pounds or more.
Among those who gained weight, the average was 4.1 pounds. Males gained an average of 4.8 pounds and females an average of 3.7 pounds their first semester at college. Seven students (3.3 percent) gained 10 pounds or more, but only one student gained at least 15 pound, a female who gained 16.2 pounds.
"It does happen," says Dr. Gropper, "even if not very often." She and her colleagues are following the 240 students throughout their freshman and beginning of their sophomore years, with questionnaires that examine factors that might contribute to the gain, however small, that the majority of college freshman appear to experience. The researchers also are collecting data on weight changes throughout the year, including five, 10, even 15+ pound losses within the first year of school.
Unique to this study, says Dr. Gropper, is the partnership with colleagues from Auburn University's Department of Consumer Affairs who use a 3-D whole body scanner to collect information on body size and shape. This technology quickly captures exact body measurements, which can be visually displayed in cross sections of body areas like the bust, waist and hips to show where changes occur in measurements over time. Understanding where weight is deposited on the body helps assess the potential risk of diseases such as heart disease and metabolic syndrome.
Dr. Gropper is a professor in the Auburn University Nutrition and Food Science Department. Her co-authors on the Experimental Biology presentation are Drs. Lenda Jo Connell, Karla Simmons, Pamela Ulrich, and Claire Zizza, along with two graduate students, Kelly Drawdy and Alisha Gaines. The study was funded by the USDA Alabama Agricultural Experiment Station.