Carbohydrates are first turned into glycogen and stored for immediate use as energy. If your glycogen stores are already sufficient then the glycogen is bound up (stored) for later use in fat cells. If there are no fat cells available to store the excess glycogen than new fat cells will be created. Rice is not nearly as complex a carb as flour, potatoes and such. More of the rice will get used as daily energy than say if you eat a lot of potatoes in a day. You don't see a lot of fat Asians and their primary source of carbs is from rice and rice makes up about 70% of their daily diet. Rice of course becomes much more fattening if you are talking about risotto, Jambalaya, Paella etc. Or even if you just add butter.
