We asked our dietitian Julia why basmati rice is the best choice of rice for people managing diabetes. She says:
It has the same amount of carbohydrates, but it has a lower gylcemic index (or GI) meaning it is better for blood glucose control.
Low GI foods cause carbohydrates to be digested and released into the blood more slowly, meaning blood glucose levels increase more slowly and don't reach as high levels compared to higher GI foods. In saying that the portion size is still important, because even if a food has a low GI a large portion size can still increase blood glucose levels to undesirable levels.
Overall basmati is the best choice for rice and a suitable portion size would be around 1/2 a cup cooked as an accompaniment to our meals.