Tuesday, April 5, 2011

The Addiction that Was

Sometimes I find is hard to articulate to "non foodies", just why I couldn't "push away from the table"...or how I became 327 pounds.  We all have our reasons, but I stand beside the fact that I am addicted to food.  Even now, healthy and 162 pounds, I think of food...pretty much non-stop. 

So...

I thought this article was interesting. If you would like to see it in it's original form, you can click here.  Bariatric Girl does an awesome job of posting weight loss surgery and related articles on her Facebook Page...which you can find here.

Whether eating food or simply craving it, food lovers appear to have neural activity similar to that of substance abusers, a small study suggests.


The study of 48 young women (mean age 20) found that while the women were anticipating drinking a chocolate milkshake, those with higher food addiction scores had greater activation in brain regions associated with reward than those with lower scores, Ashley Gearhardt, MS, of Yale, and colleagues reported in the Archives of General Psychiatry.


And when the women actually got to drink the milkshake, they had reduced activation of inhibitory brain regions seen on functional magnetic resonance imaging (fMRI).

"Similar patterns of neural activation are implicated in addictive-like eating behavior and substance abuse and dependence," Gearhardt and colleagues wrote.

Prior research has shown that there's an addictive process in the development of obesity, the researchers noted.

Food and drug use both result in dopamine release in the brain's mesolimbic regions, and the degree of release correlates with subjective reward from both food and drug use.

Yet no studies have examined the neural correlates of addictive-like eating behavior, the researchers said.
So they hypothesized that higher scores on a food addiction scale (the Yale Food Addiction Scale) would be associated with patterns of neural activation that are similar to substance dependence.

Gearhardt and colleagues enrolled 48 healthy young women with body mass indexes (BMI) ranging from lean to obese (24 to 40), who had been recruited for a long-term healthy weight maintenance trial.

Each woman had fMRI as they were exposed to two conditions -- anticipation of a rich chocolate milkshake versus a tasteless control solution, and consumption of the milkshake versus the tasteless control.

The researchers found that food scores correlated with greater activation in the anterior cingulate cortex, medial orbitofrontal cortex, and the amygdala when women anticipated drinking the milkshake (P<0.05).

The anterior cingulate cortex and the orbitofrontal cortex have both been implicated in motivation to eat, as well as with intake of drugs in patients with substance abuse, while the amygdala is also associated with increased motivation to eat.

Women with higher food addiction scores also had more activation in other regions associated with the anticipation of reward -- the dorsolateral prefrontal cortex and the caudate.
Yet there was less activation in the lateral orbitofrontal cortex when the women actually drank the milkshake -- an area associated with inhibitory control and ability to suppress previously rewarded responses.
Thus, the reduced activation "may be related to either less inhibitory control during intake of palatable food or a reduced satiety response during palatable food intake," Gearhardt and colleagues wrote.
Still, the study showed no significant associations between food addiction scores and BMI.

Those scores, however, were correlated with emotional eating and external eating, so the findings could have something to do with the fact that the sample was young and more metabolically healthy, the researchers added.

Gearhardt's group concluded that the study "supports the theory that compulsive food consumption may be driven in part by an enhanced anticipation of the rewarding properties of food," and that eating "may override desires to limit caloric food consumption ... resulting in disinhibited food consumption."

The researchers noted that their study had some important limitations.

For one thing, they excluded participants with eating disorders and Axis I psychiatric disorders, so few participants met the clinically significant distress or impairment criteria of the YFAS, required for a diagnosis of food addiction.

Therefore, the researchers said their work should be considered a conservative test, and future studies of the neural correlates of food addiction should include participants with more severe scores.
The team also did not measure hunger (although participants were asked to refrain from eating four to six hours prior to their fMRI session) and noted that fasting and hunger are associated with similar patterns of neural response, possibly confounding their results.

They noted the relatively small sample size and said the results would not be generalizable to men.

Gearhard and colleagues suggested that future studies should be longitudinal in design to allow for "a greater understanding of the antecedents and consequences" of true food addiction.

3 comments:

  1. I am so sure that there are brain chemicals involved in overeating, and I totally believe in the dopamine thing -- no question! I blogged about this last July or August, a blog called "Your Brain on Cake."

    This, for me, has been the best thing about the band. With the band, that anticipation of a chocolate milkshake is much less of a big deal. Easy to resist. Something is going on that has fixed this part of my brain (well, mostly, I still have my moments). But my band has to be pretty tight for this to happen. Just having a half-filled band doesn't do it - I will still salivate thinking about the chocolate shake.

    Very interesting, thanks Amy!I

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  2. Mmmmmmmmmmmmmmmmm..........milkshakes........

    Great info! Thanks for sharing!

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  3. After chocolate shake all I remember is blah blah blah. Wonder what that means.

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