Oat bran and wheat germ both provide important nutrients, such as iron, protein and fiber. However, wheat germ has more than twice as much fiber, more than three times as much iron and more than three times as much protein as oat bran. On the other hand, wheat germ contains considerably more calories per serving than oat bran.

Both oat bran and wheat germ provide dietary fiber, although wheat germ offers a good deal more. Oat bran contains 6 grams of fiber per one-cup serving, while wheat germ offers more than double that at 15 grams per one- cup serving. According to a 2002 study conducted by Tufts University researchers and published in the “American Journal of Clinical Nutrition,” a high intake of dietary fiber appears to reduce numerous metabolic risk factors for chronic disease, such as Type 2 diabetes and cardiovascular disease.

Iron is an essential mineral that the body uses to produce hemoglobin and myoglobin, the proteins largely responsible for transporting oxygen in the blood and the muscles. Both oat bran and wheat germ provide iron, but wheat germ provides considerably more. One cup of oat bran has 2 milligrams of iron, while the same amount of wheat germ provides 7 milligrams of iron.

Protein is essential to cellular growth, development and repair, and also plays a crucial role in muscle development. Both oat bran and wheat germ are good sources of protein, although wheat germ provides considerably more per serving. One cup of oat bran offers 7 grams of protein, while one cup of wheat germ nets 27 grams. Vegetarians can especially benefit from adding wheat germ to their diets as a means of consuming adequate protein.

In terms of calories, a large discrepancy exists between oat bran and wheat germ. Oat bran has only 88 calories in a one-cup serving. Wheat germ, meanwhile, contains 414 calories in a cup. If you are looking to cut down on calories or lose a few pounds, then oat bran will likely be the better choice over wheat germ.