1.I do not think that young people are healthy these days because there are a lot of tempations like chips,hambrugers,fries and juices that they are eating/drinking.
2.They should know that they are in danger and if they will continue like that they will be fat and stop drinking/eating food that is not good for our health.
3.The should eat some salads,chicken ,drink more water and do some sport.
4.First of all a healthier diet is based on their wish to be healthy.The should not give up and the need to stay fit until the end.