Levers? Brain Chem? What's Your Addiction Stimulus?
by Joan Kent, PhD
A woman whose knowledge and expertise I greatly respect was recently interviewed on a podcast about sugar addiction.
At some point, the interviewer asked what makes some people more "addictable" to sugar.
I'm paraphrasing everything, but the expert said animal studies have shown that "addictable" rats develop greater attachment to the cue for food (sugar) delivery than non-addictable rats. Addictable rats nuzzled the lever that signaled the food delivery, for example, as opposed to simply waiting for the food, as non-addictable rats did.
Is That All There Is?
I felt something was missing. Attachment to the cue (lever) is behavioral, and doesn't necessarily get to the underlying facts in sugar addiction. What made these rats develop the attachment in the first place?
I wanted the brain chem piece.
To my knowledge, here it is — and this is more about alcoholism and sugar addiction than about food addiction generally. It's based partly on work by the brilliant Christina Gianoulakis, PhD, at McGill University.
Alcoholics have a genetic trait that spans several generations. They have low levels of certain brain chemicals, so they feel 'less good' on a day-to-day basis than non-addicts. And when they consume alcohol or sugar, they show an exaggerated release of those same chemicals.
That makes sugar and alcohol extra reinforcing for addictable types. They feel lousy without sugar and Beyond Great with it.
What About the Rats?
I submit that the lever-nuzzling of the addictable rats in the study is based on this trait. For clarity, every addiction involves release of the brain chemical dopamine.
In the study, a lever appeared in the cage and signaled the arrival of food (sugar). The sugar delivery was both consistent and quick (within seconds). That created 2 events that need to occur for dopamine to be released in large quantities:
1) anticipation of a pleasurable experience.
2) a realistic chance that the experience will occur.
The lever was event #1. The consistent, quick delivery was event #2. Result: big dopamine.
Yet There's More!
Scientists now call dopamine the "anticipation molecule" because research shows it's released in large quantities when those 2 events occur. So all of the rats probably got a big dopamine hit when the lever appeared.
But what made the addictable rats nuzzle the lever – to the point of sometimes missing the food delivery?
I would add a 3rd factor: the genetic trait uncovered by Dr. Gianoulakis – low dopamine plus exaggerated release in response to a stimulus.
My take on the rats-and-lever experiment is that the addictable rats nuzzled the lever because of their lower-than-normal level of dopamine, plus their exaggerated dopamine release when the lever appeared.
The lever-nuzzlers became as addicted to the anticipation as to the sugar. Or even more so. That can happen with foods – and with people. Due to the brain chemical similarities between alcoholism and sugar addiction, I've connected the dots on this. (Blast me if you must.)
I love the neurochemical explanation of addiction because it removes all the blame from us. It makes no more sense to blame your brain for its response to sugar than to blame your eyes for their color. We got what we got.
The good news is we can do something to reverse the effects. It's about food and it's easy, so you can do it.
If you feel stuck on sugar or other foods, I'd love to help. Just visit www.LastResortNutrition.com and grab your free Empowered Eating Consult. Find out how easy it is to start moving things forward and feeling great — and great about you.
Brought to you by Dr. Joan Kent, best-selling author of Stronger Than Sugar: 7 Simple Steps to Defeat Sugar Addiction, Lift Your Mood, and Transform Your Health.