It’s no secret that junk food is bad for you. Scientists at the University of Montreal have conducted a study on junk food and more specifically, high fat food. In the study, which was published in the International Journal of Obesity, two sets of mice were fed diets with contrasting amounts of fat. The first group of mice was fed a diet that had 11% fat and the other was fed a diet with a whopping 58%. After six weeks on these diets, the scientists analyzed the brains of the mice and looked at their behaviors and emotions.
An interesting thing to note was that during the 6 week period, the mice on the high fat diet experienced an 11% increase in waist size. Furthermore, researcher Dr Stephanie Fulton observed changes in the brain chemistry of the mice. Researcher Dr Stephanie Fulton noted that the mice in the high fat group became more anxious at the end of the diet.
“The chemicals changed by the diet are associated with depression,” study researcher Dr. Stephanie Fulton said in a statement. “A change of diet then causes withdrawal symptoms and a greater sensitivity to stressful situations, launching a vicious cycle of poor eating.”
This suggests that junk food is potentially addictive. That may go some way in explaining which people experience cravings for junk food and cannot seem to stop eating it. Also, it also explains why many people have trouble sticking to healthier diets as the withdrawal symptoms pull them right back into the trap that they are desperately trying to get out of.
This change of behavior seems to have been caused by a change in brain chemistry. High fat diets seem to actually alter the way the brain reacts to food (at least in mice).
“They found that the mice fed the high-fat diet were more anxious at the end of the study, and also had higher levels of the CREB molecule, which is known to play a role in dopamine production (dopamine helps promote feelings of reward).”
This once again reinforces the notion that junk food can be potentially addictive. A large serving of junk food releases dopamine resulting in feelings of reward and satisfaction. When the diet is changed, that release is reduced and those feelings of reward and satisfaction are simply not strong enough. This then results in withdrawal symptoms and an even stronger urge to get that dopamine ‘high’ with junk food.
“Eating junk food can actually change the brain, spurring symptoms of anxiety and depression if you stop consuming it, according to a new study in mice.”
The research seems to show a link between the presence of ‘corticosterone’, a hormone that is normally associated with stress and CREB.
“CREB is much more activated in the brains of higher-fat diet mice and these mice also have higher levels of corticosterone, a hormone that is associated with stress. This explains both the depression and the negative behavior cycle,” Fulton said in the statement.”
While far less scientific, the documentary ‘Supersize Me’ went some way into highlighting the dangers of consuming junk food. Morgan Spurlok, the creator of the documentary, conducted a 30 day experiment in which he ate nothing but McDonalds food during a 30 day period. While he experienced some rather alarming physical changes, it’s the changes in his behavior that were more interesting. He experienced symptoms of withdrawal, depression and anxiety during his 30 day experiment.
Maybe this may explain why Popeye the sailor was always so insistent on eating “spinnich”, a known superfood.