Monday, March 29, 2010

Junk Food May Actually Be 'Addictive'

Source: Medline Plus (Summary by NIM)

These days, we often hear people say they know they should eat less but they just can't seem to do it. It seems that "food addiction" is pretty common but it may not be entirely the fault of the consumer - certain foods (think: junk food) may actually be addictive, according to a new study.

In the study, rats were given an unlimited supply of unhealthy food, and they continued to seek it out and eat it, even when they were no longer hungry and their feet were being shocked when they ate. Before their feet were shocked there was always a warning signal, but despite the pain and discomfort, the rats just kept eating and getting bigger and bigger. Then came the twist - their junk food was replaced with healthy food and they refused to eat it - for two weeks. They went on a hunger strike.

Another group of 'regular' rats were given normal, healthy food, with limited access to junk food and they only ate when they were hungry and never became obese. When the signal for the foot shock came on, the rats knew to stop eating, unlike their obese counterparts.

The researchers believe that 'rewarding foods', those that trigger the release of dopamine in our brains (just like drugs do) keep us coming back for more despite the negative effects to our health. Worse yet, the reward system may be overpowering our regular 'hunger-satiety' signals, blocking out signals of fullness and triggering compulsive eating. The only way to re-wire the brain to function normally again may be to eliminate all junk food from the diet and eat clean, kind of like a 'food rehab'.

Find out more about this fascinating discovery by reading the article called "Junk Food 'Addiction' May Be Real" from Medline Plus (Mar. 28, 2010).