Is Dietary Fiber Good for You? (An In Depth Look)

“It’s rich in fiber!” You have probably heard of this many times from food and nutrition advertisements. Many health professionals and dietitians stress the importance of fiber. That is because fiber is essential for maintaining good health. Dietary fiber—found in plants, fruits, and vegetables—is the portion of food that your body cannot digest. A diet with sufficient fiber provides a plethora of health benefits from constipation relief to cancer prevention.

Oats are a good source of dietary fiber. Image Credit: Jacqueline. Flickr

"Vitalize your health with a fiber-rich diet."

In addition to helping prevent heart disease and different forms of cancer, fiber also facilitates weight loss. Dietary fiber is divided into two main categories: soluble and insoluble. Soluble fiber regulates cholesterol and glucose levels. Insoluble fiber helps patients with constipation problems, and aids the movement of food through your digestive system. Both types of fibers are essential for maintaining a good health.

Quick Facts

1. Fiber prevents bowel diseases and improves circulation.
2. Improves weight loss and lowers cholesterol levels.
3. Regulates blood sugar levels and helps prevent diabetes.
4. Helps prevent heart disease and cancers.

█ 1- Improves Bowel Health

As mentioned earlier, fiber is basically the part of food your body cannot digest. Fiber makes your stool heavier and softer. Softer and bulkier stool passes through your intestinal tracts with more convenience—which minimizes your risks of constipation. Fiber may also help prevent hemorrhoids. Hemorrhoids are swollen or inflamed veins in the lowers parts of the rectum and anus. Because dietary fiber softens stool, it is an effective way to prevent hemorrhoids. Hard stool increases pressure and straining, which may worsen the pain from the swollen veins. This is substantiated by a study from the Hepato-Gastroenterology journal. In that study, researchers noticed that dietary fiber intake led to a significant decrease in internal bleeding episodes caused by hemorrhoids [1].

█ 2 - Prevents Heart Disease

Sadly, coronary heart disease (CHD) is actually one of the leading causes of death in America. CHD is characterized by the shrinkage or narrowing of the blood vessels that allow the flow of blood and oxygen to your heart. Because this  disease often develops over many decades, it can easily form without detection. Maintaining a healthy diet is a monumental step to preventing CHD. Fortunately, a fiber-rich diet may enable you to prevent CHD.

Sufficient fiber intake decreases your risk of heart disease. Image Credit: Ties Van Brussel.  

For example, a study from the Archives of Internal Medicine shows that there is an inverse relationship between heart disease and dietary fiber intake [2]. In other words, increased dietary fiber intake results in a decreased risk of heart disease. These results are fairly consistent in other studies. In fact, a study from the American Journal of Clinical Nutrition Shows that fiber not only helps prevent CHD, but also decreases all-cause mortality rates [3]. That should not be surprising, because another study from the Archives of Internal Medicine showed that every incremental 10 gram/day of fiber resulted in a 14 percent decreased risk of coronary heart disease [4].  What is more, these results are found in studies from different locations like Europe. Due to the consistent and harmonious results, it is clear that dietary fiber does lower your risk of heart disease.

█ 3 - Facilitates Weight Loss

It is a well known fact that obesity is strongly linked to heart disease, cancer, and diabetes. Yes, maintaining a healthy diet and an ideal weight allows you to prevent numerous chronic diseases that are incessantly plaguing the world's population. The consensus of scientific studies on the effects of dietary fiber on weight loss is quite impressive.

A fiber-rich diet helps prevent obesity. Image Credit: Jean Nieves. Flickr. 

An extensive study from the American Journal of Clinical Nutrition shows that individuals who consume more dietary fiber weigh less and have smaller waist sizes [5]. Consuming only about 15 grams daily, many Americans significantly increase their risk of obesity and chronic diseases. This clearly shows the importance of having a fiber-rich diet. One way dietary fiber promotes weight loss is by increasing the volume of food without increasing calories. As a result, you will feel full or satiated faster.

█ 4 - Helps Prevent Diabetes

Diabetes is a group of diseases characterized by anomalously high blood glucose levels. The most common type is type 2 diabetes. However, it is possible that foods rich in dietary fiber may help you prevent and alleviate diabetes. A study from the Archives of Internal Medicine provides promising results. Because diabetes is common among African-American women, that study utilized data from the Black Women's Health Study (BWHS)--which is a large study that constituted about 60,000 participants.

Based on the results, the researchers of the study concluded that dietary fiber may be an effective way to reduce your risk of type 2 diabetes [6]. The results from another study by the American Journal of Clinical Nutrition provide additional corroboration, because there were strong inverse associations between dietary fiber and incidence of type 2 diabetes [7]. The results from those studies show that there is a relatively firm consensus of the antidiabetic effects of dietary intake.

█ 5 - Lowers of Your Risk of Cancer

Cancer is arguably one of the leading causes of disease-related deaths in the world. There is now evidence that dietary fiber may help you prevent breast cancer, gastric cardia cancer, and colon cancer. Breast cancer itself is one of the main causes of cancer deaths in women. Studies are consistently showing that there is an inverse relationship between breast cancer and dietary fiber intake.

Dietary fiber may help prevent colon cancer. Image Credit: Wikimedia Commons.

For example, a study from the International Journal of Cancer shows that adequate fiber is associated with a significantly lower risk of breast cancer. The same results are found in many other studies [8]. In a study from The American Journal of Clinical Nutrition, researchers examined the data from other cohort studies of dietary fiber. The results showed that every incremental 10 gram/day of dietary fiber was associated with a 7 percent decreased risk of breast cancer [9].  Similar results have been found for stomach (gastric) cancer.  Some studies suggest that dietary fiber may help prevent colon cancer. However, the results have been inconsistent. That is likely due to the difference between the sources of and types of dietary fiber.

█ 6 - Treats Gallstones

Gallstones are hard stone-like deposits from digestive fluids that form inside your gall bladder. Although some patients do not experience symptoms, gallstones are often characterized by sharp pain in your abdominal area. Fortunately, dietary fiber may also help prevent gallstone disease. In a study from the American Journal of Surgery, researchers used prairie dogs to determine the efficacy of dietary fiber in inhibiting cholelithiasis (gallstone formation). The dogs who were treated with psyllium (soluble fiber supplement) had the least amount of gallstones. Similar results were found in other studies.

█ Does the Source of Fiber Really Matter?

Yes, it is very important to consider the source and type of dietary fiber. It is a veritable fact that dietary fiber does benefit your health and helps you prevent different forms of chronic diseases.. However, different sources and types (soluble and insoluble) affect your health differently. Not all plants have the same amount of dietary fiber, and there exists differences between how soluble and insoluble fiber affect cancer, heart disease, and diabetes. For example, the source of dietary fiber is strongly important when it comes to preventing colon cancer.  A guide detailing ideal sources and types of dietary fiber, and their effects on your health will soon be available.


1. Hepato-gastroenterology. "Effect of fiber supplements on internal bleeding hemorrhoids." Accessed April, 2012.

2. Archives of Internal  Medicine. "Dietary fiber intake and reduced risk of coronary heart disease in US men and women: the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study." Accessed April, 2012.

3. American Journal of Clinical Nutrition. "Dietary fiber intake in relation to coronary heart disease and all-cause mortality over 40 y: the Zutphen Study 1,2,3." Accessed April, 2012.

4. Archives of Internal Medicine. "Dietary fiber and risk of coronary heart disease: a pooled analysis of cohort studies." Accessed April, 2012.

5. American Journal of Clinical Nutrition. "Dietary fiber and subsequent changes in body weight and waist circumference in European men and women." Accessed April, 2012.

6. Archives of Internal Medicine. "Glycemic index, glycemic load, and cereal fiber intake and risk of type 2 diabetes in US black women." Accessed April, 2012.

7. American Journal of Clinical Nutrition. "Carbohydrates, dietary fiber, and incident type 2 diabetes in older women." Accessed April, 2012.

8. International Journal of Cancer. "Dietary fiber intake and risk of postmenopausal breast cancer defined by estrogen and progesterone receptor status--a prospective cohort study among Swedish women." Accessed April, 2012.

9. American Journal of Clinical Nutrition. "Dietary fiber intake and risk of breast cancer: a meta-analysis of prospective cohort studies."  Accessed April, 2012.

10. American Journal of Surgery. "Soluble dietary fiber protects against cholesterol gallstone formation." Accessed April, 2012.