If you are an emotional eater, pay attention: A new study says that eating lots of high-calorie, high-fat or high-sugar foods trigger the same areas of our brain that drugs like cocaine or heroin do, and actually can trigger food addictions and compulsive eating.
The research, which was done with rats and published in this week’s Nature Neuroscience, was studying obesity and how to treat it. It found that rats who were fed a healthy diet but also allowed all the high-calorie food they wanted soon developed a preference for the high-calorie food, became obese and turned into compulsive eaters with addiction-like responses in their brains.
The researchers also found that levels of a brain chemical that allows us to feel reward – a specific dopamine receptor – were lower in the overweight rats. This same condition was found in humans addicted to drugs.
Translation?
If you find yourself constantly craving and eating food that you barely taste and aren’t really hungry for, this may be an explanation.
Doing drugs such as cocaine and eating too much junk food both gradually overload the so-called pleasure centers in the brain, lead researcher Paul J. Kenny, Ph.D., an associate professor of molecular therapeutics at the Scripps Research Institute, in Jupiter, Florida, told CNN. Eventually the pleasure centers "crash," and achieving the same pleasure – or even just feeling normal – requires increasing amounts of the drug or food, he said.
"People know intuitively that there's more to [overeating] than just willpower," he says. "There's a system in the brain that's been turned on or over-activated, and that's driving [overeating] at some subconscious level."
An estimated two-thirds of American adults and a third of American children are overweight or obese today, according to the Centers for Disease Control and Prevention. More from the Reuters story:
"Obesity may be a form of compulsive eating. Other treatments in development for other forms of compulsion, for example drug addiction, may be very useful for the treatment of obesity," Kenny told Reuters news service.
"We basically bought all of the stuff that people really like -- Ding-Dongs, cheesecake, bacon, sausage, the stuff that you enjoy, but you really shouldn't eat too often," Kenny said.
They also bought healthy foods and devised a diet plan for three groups of rats.
One group ate a balanced healthy diet. Another group received healthy food, but had access to high-calorie food for one hour a day. Rats in the third group were fed healthy meals and given unlimited access to high-calorie foods.
More from the CNN story:
Not surprisingly, the rats that gorged themselves on the human food quickly became obese. But their brains also changed. By monitoring implanted brain electrodes, the researchers found that the rats in the third group gradually developed a tolerance to the pleasure the food gave them and had to eat more to experience a high.
They began to eat compulsively, to the point where they continued to do so in the face of pain. When the researchers applied an electric shock to the rats' feet in the presence of the food, the rats in the first two groups were frightened away from eating. But the obese rats were not. "Their attention was solely focused on consuming food," says Kenny.
In previous studies, rats have exhibited similar brain changes when given unlimited access to cocaine or heroin. And rats have similarly ignored punishment to continue consuming cocaine, the researchers note.
And when the high-calorie food was taken away and replaced with more nutritious options, the rats balked, Kenny told the London Telegraph.
"When we removed the junk food and tried to put them on a nutritious diet – what we called the 'salad bar option' – they simply refused to eat.
"The change in their diet preference was so great that they basically starved themselves for two weeks after they were cut off from junk food."
Dr Kenny said the research supported what obese patients have been saying for years that, like addiction to other substances, junk food binging is extremely difficult to stop.
The CNN Health story:
http://www.cnn.com/2010/HEALTH/03/28/fatty.foods.brain/
The Reuters story:
http://www.reuters.com/article/idUSTRE62R23O20100328
From Telegraph.co.uk:
http://www.telegraph.co.uk/health/healthnews/7533668/Junk-food-as-addictive-as-heroin-and-smoking.html