Carbohydrates are the most common source of food energy. Our grandparents lived quite well on diets high in unrefined or natural carbohydrates - vegetables, fruits, and whole grains. These foods supplied starches, natural sugars, vitamins, minerals, plant chemicals, and adequate fiber to keep everything in good working order. So why do some people (especially dieters) fear and avoid carbohydrates today?
The question has many sides to it, and lack of understanding is rampant - the old potatoes are fattening" myth, for example. The most important point to remember about carbohydrates is that there is a significant biochemical difference between unrefined carbohydrates (like potatoes and other vegetables, for instance) and refined carbohydrates, such as bleached-flour bread or pasta, white rice, and sugar.