Some people may see in some movie the plots that the heroes will eat some of their favorite foods to change their low spirits or some people themselves have the same experience. For example, some say that when they are in low spirit, they would take in a lot of candies to ease their depression. It is true that foods will really have some effects on peoples emotion.
There are three main chemical ingredients in foods; they are carbohydrates, protein and fat. Their impacts on people's feelings are not the same. Although carbohydrates have little effect on clinical severe depression, but they seem to be able to help people resist the daily "depressed" mood. The reason is simple: the human body uses carbohydrates to produce a 5 - HT --- a key regulator of emotions in brain. There is a protein tyrosine, which can promote brain norepinephrine and dopamine synthesis and both of these two chemicals can ease stress, improve memory and understanding, so the students can eat more foods such as fish , meat which are rich in protein during the examination. Up to now, no scientific evidence has shown that fat can have an impact on short-term sentiment. The immediate effect may not be obvious, however, high fat diet may have long-term effects on people's mental state. Many obese people say they will be "drunk" when they eat the food because sometimes people will fall because of the high-fat foods and even a mental recession will happen.
There are other more emotional effects that the foods may have, and many people unconsciously know that. Therefore, when people are in depression, they are usually inclined to use foods to improve mood. Experts in both nutrition and psychological field have probed into a further research in the relationship between foods and emotions. It is highly recommended that people should think twice before they choose their menu. The key lies in that people should choose the proper foods that they need. Only in this way can they maintain a good mood after they have eaten the foods they choose.