Dietary Fiber: Essential for Good Health
By Keri Peterson, MD —
Dietary fiber is an essential part of our diet and plays an important role for our health.
What is fiber?
Fiber is a type of carbohydrate found in plant foods and grains that our body cannot digest, so it passes through our intestines rather than being absorbed. It can be classified into two different types, soluble and insoluble. Soluble fiber dissolves in water and is fermented by bacteria in our intestines. Insoluble fiber does not dissolve in water and as it goes through our intestines it stays relatively intact.
Each type of fiber has numerous health benefits and can be found in a variety of foods. Insoluble fiber promotes movement of food through our intestines and bulks the stool. Bulking the stool helps the bowel to contract and push the stool through the intestines more easily. This can be very helpful for people who struggle with constipation as it promotes regular bowel movements. Insoluble fiber can be found in many foods like wheat bran, whole grains and vegetables like green beans and cauliflower.
Soluble fiber reduces the risk of developing several conditions. It has been linked to a lower risk of heart disease in a number of studies. Additionally, soluble fiber lowers blood cholesterol and reduces the risk of certain cancers like colon cancer and breast cancer. It is of benefit in diabetics as well by lowering blood sugar levels and insulin response. Fiber also aids in weight management as it helps with satiety and allows us to feel full and reducing appetite. Soluble fiber can be found in oats, bran, beans and psyllium fiber.
The Fiber Gap
The recommended daily intake of fiber is 38 grams per day for adult men and 25 grams per day for women. Yet most of us do not meet these intake guidelines on a daily basis. The under-consumption of fiber compared to the recommended daily intake is what is known as a “fiber gap.” One reason some people do not take in enough fiber is that there is a misconception that it can cause stomach upset or constipation. If you rapidly increase your fiber intake this may happen, so gradually increasing your intake is recommended. Also, be sure to drink lots of water to avoid constipation. Try to eat a variety of fiber containing foods that contain both soluble and insoluble fiber. This will allow you to get all the fiber you need without any uncomfortable side effects.
What You Can Do
To fill your fiber gap eat plenty of fruits, beans, vegetable and whole grains. There are many different forms of fiber. Fiber such as oat beta-glucan can be found in oatmeal while chicory root fiber and inulin is found in cereals and granola. Soluble corn fiber (also listed on ingredient panels as resistant maltodextrin) and Polydextrose are other sources that are added to a wide variety of foods like dairy products, sauces and snacks- just look for them on the label. You can also enjoy many fiber enriched foods such as whole wheat bread and grain cereals.
You can find the amount of dietary fiber in a product on the Nutrition Fact label. First look for the total carbohydrates on the panel then look below it, fiber will be listed just underneath it because fiber is a type of carbohydrate. In the right column you will find the percent daily value that the amount of fiber contained in the product represents. If it is 20 percent or higher then it is a good source of fiber.
Keri Peterson, MD is a medical contributor and columnist for Women’s Health and a frequent guest on NBC’s Today, ABC’s Good Morning America, Fox News and CNN. Based in New York City, Dr. Peterson has been in private practice since 1999 and holds appointments at Lenox Hill Hospital and Mount Sinai Medical Center. With a BA from Cornell University and a Medical Degree from Mount Sinai School of Medicine, she completed post-graduate training in Internal Medicine at New York’s Mount Sinai Medical Center and is board certified in Internal Medicine. Dr. Peterson is a member of the American College of Physicians and the American Medical Association, and serves as a medical advisor for the Calorie Control Council.