There has been a lot of talk in recent years over which substance is truly beneficial to losing weight and a healthy diet when you get rid of it. The debate over whether sugar is just as bad or worse than fat has been ongoing and in an attempt to work out which affects our health and weight more, two men took on an interesting experiment.

Identical twins Xand and Chris van Tulleken embarked on an experiment that would help to determine whether a low sugar or low fat diet is better. Chris went on a high-sugar, low-fat diet, while Xand changed his diet to the opposite. It was thought that the fact that they are identical would help to compare both diets more accurately.

The experiment was filmed for BBC 2's Horizon, which showed Chris eating a diet that contained a high amount of carbs. While he was able to eat a lot, he was still hungry, in comparison to Xand who had a high protein diet that helped him to feel fuller for longer. 

This difference in appetite is down to the way that fat and sugar affect ghrelin, the hunger hormone. Monounsaturated and polyunsaturated fats actually helped to suppress Xand's appetite, but a single gram of these fats has double the amount of calories as a gram of sugar and the calories are turned into fat more easily.

As the diets progressed, both twins felt tired and slow and didn't enjoy their meals as much. Chris also found that he became less resistant to insulin on his no-sugar diet, which could cause diabetes in the long run.

In the end, it would seem that both diets proved beneficial to weight loss, with both twins weighing in lighter at the end of the month - although Xand had the more substantial weight loss. However, despite the loss in pounds, the pair had encountered problems when it came to cutting out sugar or fat.

The experiment would suggest that getting rid of one or the other is not the best way to diet. Instead maintaining a healthy balance of both - after all you body needs small amounts of both sugar and fat to continue functioning - seems to be the best answer. Keeping track of sugar and fat intake can help you to lose weight steadily, while also maintaining energy levels and leaving you feeling fuller for longer.