The scientists reveal what they have discovered about four of the country's most popular diets in the conclusion of the weight-loss study. Showing which diets worked best, they also address the question of how slimmers can find the regime which is best suited to their needs. Eamonn Holmes talks to those who made the most significant losses, and there's also a look at what will happen to the trials' participants in the future. www.bbc.co.uk/diettriais