Over the last several years, there has been a slow but steady change to the recommendations for good health, whether it is for weight loss, cancer prevention, or general wellness. The common denominator to most recommendations is the emphasis on dietary fiber. You may have heard recommendations for adding more whole fruit or vegetables or using more whole grains. Your grandparents may have called it roughage, and it is a major player in the arena towards good health. Most Americans do not get adequate fiber, nor do many understand the types of fiber available or the roles fibers play in health.
Getting Rough with Your Diet
By Pamela Cannoy Kelle, RD, CDE
What Is It and Where Is It?
Fiber is essentially carbohydrate that is not absorbed by the body. Sources of dietary fiber are usually divided according to whether they are water-soluble or insoluble. Both types of fiber are present in most plant foods in different amounts. You can see the degree of fiber potential a food has based on the plant’s characteristics such as the stalks, stems, roots or leaves, hulls and shells.
Insoluble fiber (or roughage) has increased bulk and is more rigid in appearance; it moves through the intestinal tract fairly intact and undigested. Insoluble fiber has the ability to absorb water and, therefore, aids transport through the intestinal tract. The skin or outer shell is insoluble, and examples include the outer layers of bran in whole wheat, the outer layer of corn, flax seeds, and legumes.
Soluble fibers, on the other hand, undergo metabolic processing by fermentation and dissolve in water. The gel-like consistency has significant health implications. For example, by binding to fatty substances, soluble fiber can help lower cholesterol and help regulate the body’s sugar levels. Think of oatmeal: the outer oat bran is insoluble fiber, while the inside of the dissolved oat has soluble fiber that will ferment in the large intestine.
Why We Need to Rough It
Fiber helps our bodies to:
• Stabilize blood glucose levels
• Suppress cholesterol synthesis by the liver and reduce blood levels of LDL and triglycerides (especially cereal fibers such as oats and whole wheat)
• Decrease the formation of colon polyps
• Increase absorption of dietary minerals
• Possibly help immune function
• Increase proliferation of “good” bacteria in the colon for intestinal health
• Decrease constipation
Constipation is the most common gastrointestinal complaint in our country. The gastrointestinal tract is highly sensitive to dietary fiber, and consumption of fiber seems to relieve and prevent constipation. The fiber in wheat bran and oat bran seems to be more effective than similar amounts of fiber from fruits and vegetables. Experts recommend increasing fiber intake gradually rather than suddenly to avoid stomach distress from bloating. It is important to remember to increase liquids because fiber absorbs water.
Weight Loss and Fiber Management
A diet high in fiber produces other very important benefits. Recent studies have shown that a diet that falls into the category of low glycemic index (which essentially means high fiber) will aid fullness, decrease spikes in blood glucose levels, increase satiety, and, therefore, keep hunger from returning as quickly. This has very important implications to both diabetes management and potential weight loss. Foods that have a high glycemic index may not control hunger as well. Some examples include potatoes, refined foods such as white bread, white rice, refined cereals (corn flakes, Cheerios), white spaghetti, and sugar. Because foods with a low glycemic index do not raise blood sugar levels as quickly, consumption is encouraged in order to decrease the risk of type 2 diabetes. People who consume high fiber foods tend to be able to control weight more easily. Low glycemic index foods include legumes, 100 % whole-wheat flours, bran, barley, and some vegetables, including green beans and sweet potatoes.
Reading Labels and Shopping for Fiber
It is important to select your food products not only by the looks, but also by the label. Just because it’s brown, that does not mean it’s whole wheat. By law, bread labeled “whole wheat” must be made from whole-wheat flour. The fiber content is listed on the Nutrition Facts panel under the Total Carbohydrate heading. Fiber listed as 5 grams or more is considered significant and should be one factor in your criteria for food selection.
Many area bakeries and grocers carry specialized high fiber foods. Greenlife Grocery, for example, has many fresh-baked products specifically formulated with whole grains and that are higher in fiber than the typical manufactured bread and cereal products. Dream Dinners here in Chattanooga has also made available a variety of dishes with high fiber alternatives. Owner Liz Davenport says it’s important to her guests to know that the highest quality foods are available and recipes can be modified to increase fiber content. Today, many of her guests ask for information concerning the fiber content and request the whole wheat, brown rice, and other alternative selections. On their website, fiber content is listed, as are all other nutrients.
How Tough Is It to Be Rough Enough?
According to Harvard School of Public Health Nutrition, current recommendations suggest that adults consume 21-38 grams of dietary fiber per day, depending on age and gender. Children ages one and up should consume at least 19 grams of fiber per day. Yet even the average American eats only 15 grams of dietary fiber a day. The rule of thumb is to consume 14 grams of fiber for every 1,000 calories of food eaten. Some even recommend 30 grams for all adults. Remembering to include enough water as you increase the fiber in your diet is also important.
It is interesting to note that if Americans followed the recommendations for whole grains, whole fruits and vegetables daily, they would be consuming nutrient rich foods and, at the same time, decreasing the risk of obesity and diabetes. There is no question…it’s time to get rough with our diets.
Pamela Kelle, RD, CDE, is a nutrition therapist and registered dietitian. She is in private practice in Chattanooga. Pam works with individuals and groups with weight-related issues and diabetes. Her office is located in the historic Southern Saddlery Building on South Broad Street. She can be reached at 423-752-5207 or at firstname.lastname@example.org.