There are considerable variations in published figures for the vitamin content of wheat, but the grain is considered to be significant source of the vitamins thiamin, niacin, and B6.
The content of vitamin A is known to be negligible, but the germ is one of the richest known sources of vitamin E.
Cereals may supply the entire requirements of vitamin E, provided the grain is used quickly after processing to prevent the development of rancidity and off-flavor.
Except for yellow maize, cereals, are low in carotene and vitamin A and are deficient in vitamin D and most of the B vitamins, thiamin excepted. Cereal also low in riboflavin.
Maize, oats and rye are much lower in niacin than are barley and wheat, with only about one-third of the niacin being available.
The vitamin content of cereal products varies with the degree of processing of the grain.
As the vitamins are found largely in the germ and outer layers of cereals, removal of these on milling will reduce the amounts left in the food as eaten.