Brain Response to Eating the Same Foods

One potential contributing factor to increasing rates of overweight and obesity is the availability and affordability of a wide range of food choices.  A variety of inexpensive fast food options provides consumers the ability to rotate restaurant selection and reduce the risk of monotony in food selection.


Animal studies demonstrate that animals provided the same types of food (or other types of rewards) tend to reduce the level of consumption.  This is a behavioral trait known as habituation.  Habituation represents the tendency to  reduce total caloric intake when eating the same foods and to increase caloric intake when presented novel food choices.


Food habituation in humans has received limited attention.  For example, it is unclear whether being presented the same food weekly results in habituation.   Additionally, it is unclear whether food habituation occurs in similar manner for those who normal weight compared to those who are overweight.

Understanding habituation in humans may provide an insight in how to use food presentation to reduce or increase caloric intake.

Epstein and colleagues recently published a simple but important study of food habituation in a group of normal weight and obese women in the American Journal of Clinical Nutrition.  The study design was relatively straightforward.  Each group of normal weight and obese women were divided in two and were studied in one of two longitudinal experiments:

• Daily group: Every day for 5 days over the lunch hour, women in this group were brought into the lab and provided an opportunity to earn a 125 calorie portion of macaroni and cheese.  Subjects could decide to persist for up to 14 portions over 28 minutes or if they elected they could leave the food station and attend to a station where a newspaper and Sudoko puzzles were available.
• Weekly group:  The weekly group performed an identical experiment except they attended once a week for five weeks

So the experiment essentially tried to determine how enticing a single food (macaroni and cheese) was when offered on a daily compared to a weekly basis.  The key results of the study were:

• Women presented daily macaroni and cheese reduced caloric consumption of mac and cheese by about 100 calories from day 1 to day 5 and reduced their rating of how much they liked mac and cheese over the course of the study
• Women presented weekly macaroni and cheese increased caloric consumption of mac and cheese by about 100 calories from week 1 to week 5
• The pattern in obese women looked identical to that found in women of normal weight

So, if you are interested in losing weight, eating the same thing daily may be a way to use the habituation process to aid calorie restriction.  However, if you eat the same thing every day you do need to worry about the nutritional profile of what you are eating.  Appetite and drive for specific foods may be a biological mechanism to assure intake of all necessary nutritional components.

This study confirms that humans, like animals develop food habituation when presented the same food daily.  Habituation does not appear to be influenced by being obese.  It is unclear why this biological process develops.  Perhaps it is a mechanism to encourage exploration for novel foods that may add nutritional diversity.

Photo of sunrise at Juno Beach, Florida from author's collection.

Epstein LH, Carr KA, Cavanaugh MD, Paluch RA, & Bouton ME (2011). Long-term habituation to food in obese and nonobese women. The American journal of clinical nutrition, 94 (2), 371-6 PMID: 21593492