Genetically - modified crops have many benefits .They can protect attacks by pests . Also some GM crops work like medicines . GM crops could solve the problem of starvation . However , Genetically modified crops have a disastrous effect on agriculture and the environment in general . They might , for example , kill natural plants and take over from them . Also , people say that we do not know enough about the effect of GM food on the human body . GM food causes dangerous problems to our health .