Whole Grains and Fiber

Any food made from wheat, rice, oats, corn, or another cereal is a grain product. Bread, pasta, oatmeal and grits are all grain products. There are two main types of grain products: whole grains and refined grains. 

  • Whole grains contain the entire grain – the bran, germ and endosperm. Examples include whole wheat, oats/oatmeal, rye, barley, corn, popcorn, brown rice, wild rice, buckwheat, teff, triticale, bulgur (cracked wheat), millet, quinoa, and sorghum.
  • Refined grains have been milled and processed in a way that the bran and germ are removed. This gives refined grains a finer texture and improves their shelf life. This process removes some important nutrients, including B-vitamins, iron, and dietary fiber. Some examples of refined grains are white flour, white bread, and white rice. Most refined grains are enriched, which means that some of the B vitamins and iron are added back after processing. Fiber, however, is not added back to enriched grains. Some examples of enriched grains are enriched white flour, enriched white bread, and enriched white rice.

Eating whole grains provides important health benefits.

Many whole grains are good sources of dietary fiber. Most refined grains contain little fiber. Dietary fiber from whole grains, as part a healthy diet, may help improve blood cholesterol levels, and lower risk of heart disease, stroke, obesity and type 2 diabetes. Dietary fiber can make you feel full, so you may eat fewer calories. Including whole grains in your diet plan may help you reach or manage a healthy weight.

Dietary Fiber

Dietary fiber is the term for several materials that make up the parts of plants your body can’t digest. Fiber is either soluble or insoluble.

Soluble fiber

  • Soluble fibers are able to swell and hold water.
  • When eaten regularly as part of a diet low in saturated fat and trans fat soluble fiber has been associated with better diet quality and lower risk of heart disease.
  • Soluble fiber reduces LDL (“bad”) cholesterol beyond what a diet low in saturated and trans fats can do alone.
  • Oats are a good source because they have a greater proportion of soluble fiber than any other grain.

Insoluble fiber

  • Insoluble fiber has been associated with lower cardiovascular risk and slower progression of heart disease for people who are high-risk.
  • Wheat, rye, rice, and most other grains are mostly composed of insoluble fiber.

Beans and peas are also excellent sources of both soluble and insoluble fiber. Many processed oat bran and wheat bran products (such as muffins, chips, waffles) may be made with refined grains, not the whole grain. They also may be high in sodium, added sugars and saturated fat. Read labels carefully.

Grains are also important sources of many nutrients.

  • B vitamins (thiamin (Vitamin B1), riboflavin (Vitamin B2), niacin (Vitamin B3), and folate (Vitamin B9) are important in a variety of biological functions.
  • Folate (folic acid), one of the B vitamins, helps the body form new cells and can prevent certain birth defects.
  • Iron is used to carry oxygen in the blood.
  • Magnesium is a mineral that is involved in more than 300 processes in the body.
  • Selenium is important for a healthy immune system and the thyroid.


It’s important to eat many types of grains because grains they have different nutrients. Whole grains can be a good source of fiber, but refined grains usually are not. Whole grains are eaten either as a single food (e.g., brown rice, popcorn) or as an ingredient in a complex food (e.g., in multi-grain breads). 

Whole grains cannot be identified by the color of the food. Bread, for example, can be brown because of molasses or other ingredients, not necessarily because it’s made with whole grains. That’s why it’s important to read the ingredient list on the food nutrition label. For many whole-grain products, you will see the words “whole” or “whole grain” before the grain’s name in the ingredient list. The whole grain should be the first ingredient listed.

Choose whole grain foods that contain one of the following ingredients first on the label’s ingredient list:

  • whole wheat, graham flour
  • oatmeal
  • whole oats
  • brown rice
  • wild rice
  • whole-grain corn
  • popcorn
  • whole-grain barley
  • whole wheat bulgur and whole rye.

When grocery shopping, an easy way to identify healthy food choices is to look for the Heart-Check mark on food labels.

Getting the Right Amount Counts

How many servings of grains do you need each day? It depends upon your age, gender, and calorie needs. The American Heart Association and the Dietary Guidelines recommend that at least half of your grains are whole grains.

Serving Size

The following count as 1 ounce-equivalent (or 1 serving) of whole grains:

  • 1 slice whole-grain bread (such as 100% whole-wheat bread)
  • 1 cup ready-to-eat, whole-grain cereal
  • 1⁄2 cup cooked whole-grain cereal, brown rice, or whole-wheat pasta
  • 5 whole-grain crackers
  • 3 cups unsalted, air-popped popcorn
  • 1 6-inch whole-wheat tortilla

 Thanks to the AHA for this important information.