The Mechanism that links Obesity and Addiction

When an animal finds food in the wild, it is a rewarding stimulus for the animal and is recognized by the brain by the release of dopamine.

Illicit substances such as cocaine, heroin and amphetamines also cause the release of dopamine and therefore make people feel rewarded when they take drugs. The release of dopamine also occurs in tasty and highly-caloric foods. For this reason it's clear that dopamine has a role in addiction and the development of obesity.

Professor Bill Colmers set out to find if dopamine may have an effect on the memory-forming brain cells in the dentate gyrus. 'Conditioned Place Preference' is the name given to the behaviour when an animal knows it can expect rewarding stimuli, like a treat, in a certain location. This forms spatial memories in the dentate gyrus.

They found that when dopamine was added, it increased the excitability in part of the brain cell called the dendrites. A chemical secreted by the brain, Neuropeptide Y, had the opposite effect making the cells less excitable.

"You can find the fridge and you know there's good stuff in there, so you can find it in your sleep, and people do," said Colmers. "So there's this whole reward aspect to place that we've been able to unravel."

---

So if location and 'reward' can be linked, then avoiding places where we usually have a 'treat' (e.g. not going to the employee lounge on our breaks!) may help reduce those cravings for high-calorie foods. Similar findings have already been talked about in regards to drug use, (e.g. smokers not sitting outside can help curb the need to smoke) but with this finding used to explain eating behaviour and obesity, it shows how obesity and drugs addiction are not worlds apart.

Link to Article