One of the pioneers of using GI (glycaemic index) in relation to weight loss was Frenchman Michel Montignac. His diet has a large number of followers and is based on the glycaemic index of foods as well as food combinations. According to Michel Montignac, combining certain foods makes you fat, and ultimately we dont put on weight by eating too much but by eating badly. He sees weight gain as being linked to eating bad carbohydrates and bad food combinations.