Firstly, such food is low in protein, vitamins and minerals. Cholesterol causes the production of a fatty plaque that clogs the arteries, which can lead to a heart attack or a stroke.
Thirdly, fast food is high in fat, sugar and calories and full of chemical additives.
For example, a can of Coke contains about eight teaspoons of sugar and artificial sweeteners.
People who are used to consuming several cans a day may suffer from diabetes, cancer and tooth decay.
They may become overweight or obese, which can lead to heart disorders and other health problems.
Secondly, GM crops provide benefits to the environment through a reduction in the use of pesticides.
In addition, the recent rapid increase in human population has raised concerns that we will not be able to provide everybody with food.
Nevertheless, some people think that it is cruel to eat animals.
Apart from that, they say that a properly planned vegetarian diet is good for your health and helps to prevent certain diseases.