Overeating for just four weeks can cause changes in body fat composition that last for years, Swedish researchers said Tuesday. The study serves as a warning that even brief periods of increased food consumption -- the first few weeks of college dorm life, a three-week cruise with its all-you-can-eat buffet, the string of parties from Thanksgiving through New Year's -- should be avoided.
Swedish researchers recruited 18 healthy, young adults who had normal body weights for the study. The participants were instructed to limit their physical activity to 5,000 steps a day or less, which is considered a sedentary lifestyle. They were also told to increase their caloric intake by 70% for four weeks. Most of them did this by eating two fast-food meals a day. The researchers then compared this group with a control group -- a similar group of young adults who did not change their diet or physical activity. The groups' body weight and composition were examined periodically for two years.
The people who increased their food intake for four weeks gained an average of 14 pounds. There were large individual differences in weight changes, but after six months, only one-third of those participants had returned to within one pound of their initial body weight. At the one-year mark, the gluttony group was an average of 3.3 pounds. heavier than before their four-week binge while there was no change in the body weight of the control group. The binge group also had an increased fat mass and higher LDL cholesterol levels one year after their four-week binge which the control group did not experience. After 2.5 years, the group that binged for four weeks had continued to gain weight while weights in the control group were stable.