Reader of these pages are by now probably quite familiar with the complexity of ingestive behaviour and the importance of understanding brain function in relationship to food intake.
A study, published in this month’s issue of Obesity, illustrates how differences in brain function between obese and non-obese people can explain important differences in response to food.
In this study, Laura Martin and colleagues from the Kansas Medical Center, used functional magnetic resonance imaging (fMRI) to examine changes in brain activity in obese and normal weight adults while they viewed food and nonfood images in premeal and postmeal states.
Both in the premeal and postmeal state, obese participants showed showed increased activation in the anterior cingulate cortex (ACC) and the medial prefrontal cortex (MPFC), regions of the brain responsible for the reward response and impulsiveness, respectively.
In addition, activation of the ACC was associated with decreased levels of self-reported disinhibition while MPFC activation was associated with increased self-reported hunger amongst obese participants.
These findings clearly suggest that brain function associated with food motivation differs in obese and non-obese adults and may well explain the different susceptibilities to weight gain and variability in response to diet interventions.
Given the emerging science on brain plasticity, it is certainly of interest whether or not these differences in brain function are acquired or are indeed innate. Whatever the case, we need to understand and acknowledge that our brains respond differently to the same food stimuli which easily explains why some people may find it much harder to resist overeating in our current obesogenic environment than others.
As I have said before, the obesity epidemic is simply the natural response to our unnatural environment.
AMS
Edmonton, Alberta
In The News
February 24th, 2010 at 9:03 am
This article shows us that we are all different. Our spirit leads us on a path we have chosen for ourselves. Our individual reactions to foods are just that, individual. What makes us the same keeps us all different.
Interesting observations Dr Sharma.
Thank you for giving all this food for our brains. Let us all find solutions that are great for each one of us.This sentence should be remembered always:the obesity epidemic is simply the natural response to our unnatural environment. So true
Pierre for the Thee Quest team
February 24th, 2010 at 9:23 am
For reasons I can’t begin to fathom the authors did not control for the macronutrient content of their pre-test breakfast.
Given the very real importance of macronutrients in satiety this was a tremendous oversight which makes it more difficult for me to get excited about the findings.
February 25th, 2010 at 2:47 am
A test or short study doesn’t give consideration to the adaption that occurs with dietary change that includes adequate nutrition and adequate protein. When I changed from depending on a lot of pasta and bread to more protein my lab tests would have shown my adaption after a couple of months. I wasn’t driven towards carbs and was more satisfied by yummy colourful veg vs beige starch! We and our bodies can adapt and change preferences beyond initial habits.
March 30th, 2010 at 2:58 pm
Appreciate this article
May 11th, 2010 at 4:43 pm
Thank you for all you do.