High Fat, Energy Dense Foods Can Be Addictive

Our dietary habits are influenced by many, many factors.  Among those factors are the availability and palatability of food.  New obesity research examined how the availability of high fat, energy dense foods (cheesecake, pound cake, chocolate, bacon, and sausage) affected eating behavior and brain changes in rats.

In this new study, free to read online or download, researchers divided rats into the three following dietary groups for 40 days:

1. No access to the energy dense food and fed only standard rat chow
2. Restricted access to energy dense food for 1 hour per day with access to rat chow for the rest of the time
3. Extended access to energy dense food (> 18 hours per day)

During and after this 40-day test period, rats were examined for changes in eating habits, body weight, and brain biology.  Some of the changes the researchers observed in these rats included:

• Body weight increased dramatically in the rats with extended access to energy dense food compared to the two other groups of rats.
• Caloric intake nearly doubled in the rats with extended access to energy dense foods.
• Rats given access to energy dense foods for one hour per day developed binge eating habits such that about two-thirds of their caloric intake occurred during their one hour access to the high fat foods.
• Rats given extended access to these foods consumed nearly all of their calories from these foods and nearly ignored the laboratory rat chow.
• Brain measurements of pleasure/reward from eating these energy dense foods showed that over time it took consumption of greater amounts of the food to get the same level of reward.
• The decrease in the brains ability to feel reward from consuming high fat foods was related to a decrease in the number of receptors for a specific brain chemical called dopamine.

These results suggest that unhealthy eating can become habit forming.  In fact, the researchers report in their paper that the decrease in dopamine receptors seen with eating these unhealthy foods was similar to changes seen in drug addiction.  Overall, these study data suggest a self-perpetuating process where regular, long-term consumption of high fat, energy dense foods over-stimulates the brain's reward system and reduces its ability to derive pleasure from these foods, which causes us to eat more and gain weight. In this study, binge eating habits did not appear to disrupt this system nor effect energy balance; however, it is uncertain how binge eating would have effected these systems in a longer study.  While it remains uncertain how these results translate to people, they do provide some potential insight into at least one possible cause of overeating.  These study results emphasize the need for developing healthy eating habits.  If we get into a habit of giving in to our cravings, this habit of unhealthy eating can become difficult to break over time.

Eating healthy doesn't have to be difficult.  My easy plan is a great way to start developing good eating habits and help to better manage one's weight.