What is Dietary Fiber?
While folks debate the merits of carbohydrate vs. protein-focused diets, they often overlook the importance of fiber (plant roughage that is resistant to digestive enzymes). There are two types of fiber:
- Soluble fiber dissolves in water and turns into a gel, which binds to foods and carries them through the digestive tract.
- Insoluble fiber remains largely intact and provides bulk to keep food moving through the digestive tract.
Both types of fiber are needed for a smooth operating digestive system.
Why Is Dietary Fiber Important?
The National Fiber Council recommends an average of 32 grams of fiber per day, yet most Americans only consume about 10-15 grams. Aside from being more “regular,” what kinds of health benefits is the average American missing?
Eating high fiber foods is a great way to satisfy hunger without consuming too many calories. Since fiber is not digested, it does not contribute to calories consumed, yet the bulk it adds to the digestive system helps you feel full for a longer period of time.
Reduce PMS Symptoms and Risk of Cancer
The bloating, cramps, tender breasts and mood swings many women associate with their menstrual cycle are linked to the rise and fall of estrogen in their bloodstream. Women who are able to prevent their estrogen levels from rising too high are less likely to experience these symptoms. Fiber helps the body get rid of excess estrogen. Estrogen is filtered from the bloodstream by the liver and sent to the intestinal tract where fiber soaks it up and carries it out with the waste. However, if you are not consuming enough fiber to avoid constipation the waste estrogen ends up passing back into the bloodstream and may contribute to increased estrogen levels. PMS discomfort aside, high estrogen levels have also been associated with an increased risk of breast cancer.
Control Blood Sugar
One of the reasons folks are advised to eat complex carbohydrates (such as whole grains, vegetables and fruits) instead of simple carbohydrates (such as white flour products, candy and soda) is because the fiber in complex carbohydrates slows down the absorption of sugar and helps to regulate blood sugar levels. Fluctuating blood sugar levels contribute to a variety of conditions (including diabetes) with long-term consequences.
Likewise, fiber also keeps cholesterol levels in check. High fiber foods (plant-based) naturally do not add to dietary cholesterol because dietary cholesterol is only found in animal products. Additionally, the gel formed from soluble fiber entraps cholesterol components in the small intestines, which leads to a lower cholesterol count in the blood and a healthier heart.
How to Add More Fiber to Your Diet
If you are not currently eating enough fiber you will want to increase the amount of fiber in your diet gradually to avoid bloating or abdominal cramps. Begin adding more plant-based whole foods to your meals over the course of several weeks.
Great Sources of Soluble Fiber
- Whole Grains (oats)
- Vegetables (cucumbers, celery, carrots)
- Fruit (pears, oranges, apples)
- Legumes (lentils, split peas, navy beans)
- Nuts and Seeds (flaxseed)
Great Sources of Insoluble Fiber
- Whole Grains (brown rice, quinoa)
- Vegetables (zucchini, celery, broccoli, cabbage, onions, tomatoes, carrots, cucumbers, green beans, dark leafy greens & root vegetable skins)
- Fruit (berries, grapes, raisins and dried figs)
- Legumes (lentils, split peas, pinto beans, garbanzo beans)
- Nuts and Seeds
Note: Animal products do not contain any fiber. Processed foods usually contain very little fiber.
As demonstrated by the Paleo vs. Plant-based graphic shared above, even folks who think they are eating healthy may not be consuming enough fiber. The Paleo meals presented in the graphic were adapted from Paleoplan.com’s Sampler Menu. The Plant-based meals are Veggie Primer recipes and previously shared in Plant Based Nutrition Facts. The nutrition information listed in the graphic was estimated using the food log calculator on Caloriecount.com. Whether you choose to follow a plant-based diet exclusively or opt for another approach, be sure you are eating enough fiber rich foods!
- National Fiber Council
- Foods That Fight Pain by Dr. Neal Barnard
I welcome questions and comments!