Eating lots of fruit and vegetables could help protect teenagers from mental health problems, according to an Australian study published on Thursday in the scientific journal PLoS One. The study of 3,000 adolescents aged 11 to 18 found that those who had poor diets filled with junk and processed foods were more likely to suffer mental health problems such as depression and anxiety. The new research, carried out by Felic Jack from Deakin University\'s Barwon Psychiatric Research Unit in Victoria, is the first to demonstrate the link between diet quality and mental health disorder in adolescents.