Sir, Joanna Blythman, in 'Calories are not all created equal' (The Grocer, 19 March, p23), states: "Carbohydrates sugar and grains are rapidly absorbed by the body into fat." This is incorrect. The process by which carbs are converted into fat is called 'de novo lipogenesis' and rarely happens under normal dietary conditions. For it to occur, the body's significant glycgogen stores would need to be filled, and secondly the person would have to consume more than 100% of their caloric requirements from carbs. Carbs contribute to weight gain through a different mechanism, as when one eats more carbohydrates, the body burns less (and stores more) fat. 

Jonathan Goldsbrough Noble Foods