It is now extremely clear that fast-food is unhealthy. If you eat too much of it, you get fat. But do burgers, pizza and co. also have an impact on our psyche?New fast-food studyIn order to find out for sure, Richard Stevenson, a researcher at Macquarie University in Sydney, carried out an experiment involving 105 young, healthy volunteers that were split into two groups. The first of these groups lived exclusively on junk food for a period of eight days while the other group maintained their normal, healthy eating habits. And the results at the end of this eight-day period are shocking.When he see unhealthy food, we remember how good they taste and how good we feel when we eat them. When we are full, however, the part of the brain known as the hippocampus normally suppresses these memories, thus reducing our cravings for them and our desire to keep eating.Is the delicious taste really worth the consequences? Getty ImagesThe groups that ate just fast food appeared to lose their self-control. They found they had a greater craving for sweets and unhealthy food and continued to eat even when they were actually full. This study, therefore, proves that neuronal appetite regulation doesn’t work the same way when you eat these types of food.Fast food has an effect on our mental capabilitiesRichard Stevenson also noticed that fast food has a negative effect on the brain. And the bad news just keeps on coming. He observed that eating too much of this unhealthy food can cause aggression, depression, stress and can even shrink certain parts of the brain!Will this discovery be detrimental and damaging for big fast-food chains? It would definitely be the next big scandal, following the incident in which excrement was found in McDonald’s restaurants and when people realised that many of these restaurants used a toxic kitchen utensil to prepare their burgers.