A study with obese and non-obese women showed that, when macaroni and cheese was offered daily, the energy consumed decreased by about 100 calories a day. When the mean was provided only weekly, caloric intake increased by about 30 calories per day.
Researchers from the University at Buffalo and the University of Vermont report their findings in the American Journal of Clinical Nutrition .
Commenting on the findings, Nicole Avena and Mark Gold from the University of Florida wrote: “School-lunch planners and public health officials should note that diversity in the menu is not necessarily a virtue, and in fact it may be associated with promoting excess food intake and increased body mass index.”
The findings also support dietary advice for people to try to eat the same food every day, “in which case habituation may develop that would reduce the likelihood of overeating and subsequent obesity”, said Avena and Gold.
According to figures from the Centers for Disease Control and Prevention (CDC), about a third of American adults are obese, with a further third considered to be overweight.
Led by Buffalo’s Leonard Epstein, the researchers note that monotony is known to reduce food acceptability and consumption, but their study “provide[s] the ﬁrst evidence in humans that habituation may provide a theoretical explanation for why repeatedly consuming the same food will lead to reduced consumption.
“Long-term habituation, in terms of a faster rate of habituation and reduced energy intake, was observed for the daily group but not for the weekly group.
“Repeated presentations once a day compared with once a week provide a reference point for the interval between food presentations that could lead to long-term habituation,” added Epstein and his co-workers.
The study involved 16 obese and non-obese women who were randomly assigned to either the ‘daily’ or ‘weekly’ group: The ‘daily’ group received the same food on five consecutive days, whereas the ‘weekly’ group received the test meal once a week for five weeks. The women were allowed to consume as much mac and cheese as they wanted at each sitting.
Results showed that women in the daily group consumed less calories per day, whereas the weekly food exposure increased the caloric intake, and the results were the same for both obese and non-obese women.
“It is of interest that obese subjects and non-obese subjects showed similar long-term habituation to daily presentations of the same food.
“These results suggest that repeated presentations of the same [main meal] over days would be equally effective for obese and non-obese women,” wrote the researchers.
Commenting on the study, Avena and Gold said the work was “very important” but limited due to only including women.
“Thus, it will be important to further explore whether the findings obtained in the present study extend to men.”
Source: American Journal of Clinical Nutrition
Volume 94, Pages 371-376
“Long-term habituation to food in obese and nonobese women”
Authors: L.H. Epstein, K.A. Carr, M.D. Cavanaugh, R.A. Paluch, M.E. Bouton
Editorial: American Journal of Clinical Nutrition
Volume 94, Pages 367-368
“Variety and hyperpalatability: are they promoting addictive overeating?”
Authors: N.M. Avena, M.S. Gold