nos-trum. pronunciation: \nos'-trum\. noun. Etymology: Latin, neuter of noster our, ours.
1. a medicine of secret composition recommended by its preparer but usually without scientific proof of its effectiveness.
2. a usually questionable remedy or scheme.
See here for more discussion.

Tuesday, April 5, 2011

STUDY: Food Addiction Brain Response Similar To That With Drug Addiction. But...

A small study showed that anticipatory changes in the brain of food addicts are similar to those seen in drug addicts.  But this isn't to say that the two "addictive" behaviors are equivalent.

I've had my say in the past about how we medicalize all repetitive human behaviors that have negative consequences.  Addiction is one of those categories where the public and some mental health experts have expanded the definition to include almost anything:  TV-watching, shopping, exercise, web-surfing.  I'm not sure we've adequately distinguished addiction from poor choice of habit.  People argue about this endlessly.

In any case, this study showed that some women who experience an "addiction" to food have changes in their brain--as measured by MRI brain scans--when they think about delicious food that are very similar to those changes that occur when a drug addict craves the drug.

That's OK, as far as it goes, but the researchers say in conclusion:
"Similar patterns of neural activation are implicated in addictive-like eating behavior and substance dependence."
This is where ambiguity arises over the types of repetitive behavior that we class as addiction, abuse, and dependence.  The authors don't imply that brain activation makes for identical physiologic mechanisms, but the use of the word "dependence" may create a false impression that they are.

Definitions vary, but here is one way to distinguish addiction from dependence.

Addiction is a primary, chronic disease of brain reward, motivation, memory and related circuitry... characterized by impairment in behavioral control, craving, inability to consistently abstain, and diminished recognition of significant problems with one’s behaviors and interpersonal relationships

When an individual persists in use of alcohol or other drugs despite problems related to use of the substance, substance dependence may be diagnosed. Compulsive and repetitive use may result in tolerance to the effect of the drug and withdrawal symptoms when use is reduced or stopped.

I interpret this to mean that addiction is a broad, inclusive term for a behavioral abnormality.  Dependence, while included in that definition, adds an element of tolerance and withdrawal.

To put it simply, food addiction is distinct from drug addiction due to dependence.  You don't have seizures and die during withdrawal from food addiction.  Further, there's an element of food consumption that's essential to life, not present in heroin consumption.

For Onion Peelers,
Food addiction scores (N = 39) correlated with greater activation in the anterior cingulate cortex, medial orbitofrontal cortex, and amygdala in response to anticipated receipt of food (P < .05, false discovery rate corrected for multiple comparisons in small volumes).

The authors recognize that the study was very small and confined to women, limiting its broader interpretation.  But this isn't good enough.  To show similar brain activity may indicate that our "craving" mechanism is universal, but doesn't mean food--as an addiction--is parallel to drug dependence.

Until we stop throwing every repetitive behavior into the "addiction" basket, and make causative distinctions, we won't design specific--and effective--remedies for such problems as obesity and drug abuse.

Doc D

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