Fructose commonly used in fruit juices, soft drinks and snack foods, has been blamed for contributing to rising obesity and type 2 diabetes in teenagers. A new US study published in March found that fructose increased appetite. Found naturally in fruit, the sugar is used to sweeten foods and drinks. A team from John Hopkins University in Baltimore said high consumption of fructose was potentially more dangerous than other forms of sugar such as glucose because of the way it affected the brain.