White bread is bread made from wheat flour from which the bran and often the germ have been removed, in contrast to whole wheat bread made from whole wheat flour, in which these parts are retained and contribute a brownish color. In addition, this white flour is often bleached using potassium bromate or chlorine dioxide gas to remove any slight yellow color and make its baking properties more predictable.
The development of white bread was a response to the adaptation of the grocery business to modern commerce. Bleaching gives white flour a far longer shelf life than whole wheat flour, and bread made from it has a longer shelf life. This allows it to survive storage and long transit times.
White bread is often criticized for being less nutritious than other breads. Most of the vitamins inherent in wheat are removed along with the germ or destroyed in the bleaching process. In the United States, by law, white flour must be enriched with vitamins, replacing most of the major vitamins removed by bleaching - though critics claim that valuable trace minerals removed by bleaching are not replaced in the enrichment process. Counter-arguments to this claim note that the amount of trace minerals in bread is minuscule to begin with and their supply is easily substituted by other common dietary constituents such as fruits and vegetables. Most commercial white bread contains little dietary fiber when compared to bread that includes bran. A low fiber diet is linked in some instances to cases of both constipation and diarrhea. Canadian grain regulations require relatively high amounts of protein in their grain, resulting in a style of bread known as Canadian white.
White bread is also criticized for being too easily digested, resulting in more drastic rising and falling of blood sugar and insulin levels than results from eating slower digesting whole grain breads.
American bakers have attempted to respond to these criticisms with modifications to their recipes and with the proliferation of a group of "specialty" bread products. Many of these are essentially white bread with a few additives. Most commercial "whole-wheat" or "brown" bread produced in the U.S. is primarily composed of bleached white flour with the addition of enough brown flour to be brown in appearance. Bolted or "unbleached" flour has about 20% of its natural bran.
Whitebread was a pejorative term used by Soviets to refer to Americans. The term can also refer to alleged blandness or plainness in a person. Its usage is similar to that of the term plain vanilla. In the DC comic book, Justice League International, the sarcastic Green Lantern Guy Gardner would often refer to his innocent, pure-hearted teammate Captain Marvel as ‘Captain Whitebread’.