It is believed that obesity is a marker of nutrition problems. However, recent studies showed that the reason is a complete deviation in the brain. As Science Daily notes, memories inhibition (blocking of memories that are no longer needed), associated with the hippocampus, often affects nutrition. Usually food memories are updated, if a person is hungry. And when person is saturated, in contrast, memories are suppressed.
Prior studies suggest that the Western diet (rich in fat, sugar, containing little vegetables and fruits) destroys inhibition of memories in the hippocampus. In practice, it may mean that it will be difficult to suppress the pleasant memories of harmful products in response to a visual or olfactory stimulus. And the degree of saturation of a person will not play a role.
In order to clarify everything, the researchers gathered a group of volunteers and asked them to undergo tests on the learning ability and memory. It was also required to estimate the attractiveness of delicious snacks before and after a full meal. It turned out, that people who followed the Western diet pattern, cope with tests for learning and memory worse. And snacks seemed to them more attractive, despite the absence of hunger. In general we can say that harmful products adversely affect the hippocampus, which leads to a vicious cycle.