Milled rice could essentially be called white rice. Unlike typical brown rice, which has only the husk removed, it also has the rice bran layer and the germ of the rice removed. This tends to make for fluffier rice, that is usually white to light yellow in color, and is not quite as high in nutritional content.
The process for removing bran and germ is more extensive than that for preparing brown rice. In other words, milled rice is slightly more “processed” food than is brown rice. This rice tends to undergo a polishing process too, and since polishing removes most of the vitamin content of the rice, it may be enriched with vitamins in order to make up for the removed nutrients. Some countries like the US mandate the enrichment of milled rice, and require the rice to be treated with several B vitamins and iron. If these are added with powder, instructions on rice packages may suggest that you not rinse the rice, since this will result in removing these added nutrients.
Undoubtedly, brown rice is significantly better for you than milled rice, but many people still prefer the lighter taste of white rice. Milling tends to remove most of the dietary fiber. In a 3.5-ounce (about 100 g) serving of cooked white rice you get about a third of a gram of dietary fiber. This is roughly one sixth of the amount of dietary fiber you would receive if you consumed brown rice instead, which for the same serving size offers 1.8 grams of dietary fiber.
Both milled and brown rice are low in fat, and fairly low in protein. White rice is higher in calories than is brown. It has about 20 more calories per serving size than does brown, and it is higher in total carbohydrates than brown rice. From a nutritional standpoint alone, milled rice is frequently inferior, and most nutrition and diet experts recommend eating the whole grain brown rice instead.
Nevertheless, milled rice or white rice remains an important dietary staple, not just in the US but also in many parts of the world. It has old associations with being the rice of the “wealthy.” Poorer folks could not afford the extra milling process and had to eat their rice brown. In this respect, using the grain in less processed form was actually of nutritional benefit, probably one of the few instances in earlier days when the poor actually had a better diet than the rich.