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We all know that eating junk food can make us Et. However, a new study suggests that it can do more than that－it can also make us lazy.
In the study, researchers divided 32 rats into two groups. In the first experiment, the first group was fed a diet of healthy food such as com and fish, while the second was given a diet rich in sugar and fat, namely "junk food".
Within three months, the rats in the second group were already much fatter than those on the healthy diet. And when researchers trained the rats to do simple tasks, they found even more differences between the two groups other than weight.
During the task - pushing a lever to receive a prize of sugar - water the rats on the junk food diet were found to be less willing to move, and they took longer breaks between each push than the fit rats did.
"It is as if the rat is thinking 'This is too much work," said the leader of the study.
According to researchers, these differences suggest that junk food changed the chemistry in the rats' brains.
The experiments didn't end there. After six months, researchers began the second experiment. The rats' diets were changed, and the overweight rats were given a healthy diet for nine days. However, this didn't help reduce their weight or improve their ability to perform tasks. It means the effects of their junk food diet lasted for long. "There's no quick way to reduce the harm," researchers said.
For a long time, we've believed that people become fat because they are lazy. But this study has shown that the opposite is true as well. Being lazy and getting fat can go hand in hand.
So, if you always feel tired, and not willing to get up from your chair, it could be that you've been studying too hard. But you should also pay attention to your diet.
