Chances are, you've been hearing a lot in the past couple of years about the benefits of dietary fiber. But what exactly is fiber, and how can you add it to your diet easily? Learn everything you need to know about fiber right here.
What Is Fiber?
Dietary fiber is the indigestible material in plant-based foods like fruits, vegetables, beans, nuts, seeds, and most whole grains, says Lona Sandon, MEd, RD, a national spokesperson for the American Dietetic Association (ADA). Unlike the vitamins, minerals, protein, fats, and carbohydrates found in these foods, fiber is not broken down and absorbed by the body, but passes through the digestive system unchanged, and helps the body eliminate waste products.
Types of Fiber
There are two types of fiber: soluble and insoluble. Both are needed for optimum digestive health.
Soluble fiber (like pectin and gum) is found within plant cells and dissolves in water. It slows the passage of food through the digestive tract, helps reduce blood cholesterol levels, and helps stabilize blood sugar levels. Soluble fiber can be found in foods like beans, oat bran, fruits, and vegetables.
Insoluble fiber (like cellulose, hemicellulose, and lignin) can be found in the cell walls of plant foods and does not dissolve in water. Insoluble fiber increases the bulk of the stool by binding with water and softening the stool, helping it move through the digestive tract. Sources of insoluble fiber include whole grains, wheat bran, fruits, and vegetables.
Many fiber-rich foods, like oatmeal and beans, contain both soluble and insoluble fiber. As long as you include a wide variety of fiber-rich foods in your diet, ADA experts say, you needn't worry about how much of each type of fiber you're getting.
Fiber and Your Health
A high-fiber diet is known to confer many health benefits, and research reveals additional advantages all the time, Sandon says.
A high-fiber diet:
- Reduces digestive problems, including constipation, hemorrhoids, and diverticulitis
- Lowers cholesterol levels and reduces the risk of heart disease and stroke
- Balances blood sugar levels and reduces the risk of diabetes
- Aids in weight loss because foods high in fiber are more filling and satisfy hunger longer; also, fiber contains no calories
- May help reduce the risk of certain cancers, including stomach and colon cancer
High-Fiber Foods
As mentioned above, fiber can be found in many plant-based foods, including fruits, vegetables, and whole grains. Beans are particularly high in fiber, containing up to half your daily total in just one serving.
One easy way to increase your fiber intake is to switch from refined, or "white," grains to whole-grain breads, pastas, and rice, which contain significantly more fiber per serving. Compare different brands' nutritional labels to find the most fiber per serving.
When it comes to fruits and vegetables, fresh, frozen, and canned all contain the same amounts of fiber. When choosing frozen or canned products, the healthiest choices are brands that are low in sodium, sugar, and other additives. Fruits and vegetables prepared with the edible skin on contain more fiber than peeled ones. Fruit and vegetable juices contain little or no fiber, so opt for a whole carrot or an orange, for example, over juice.
How Much Fiber Do You Need?
If you're like most Americans, you're eating only about half the amount of fiber you should. Studies show that the average person eats between 12 and 14 grams of fiber a day. The FDA recommends an intake of 11.5 grams of fiber per 1,000 calories, or 25 grams per day for a 2,500-calorie diet. While that may sound like a lot, people can usually meet this daily requirement by eating several servings of whole grains, fruits, vegetables, and dried beans a day, Sandon says.
Check labels, as well. Foods with 5 or more grams of fiber per serving can be labeled "high fiber," while foods with 2.5 to 4.9 grams of fiber per serving can be labeled, "A good source of fiber," under the FDA's food labeling law.
Adding More Fiber to Your Diet
Working more fiber into your diet just takes a little creative thinking, say ADA experts. You can easily add frozen vegetables to soups; top sandwiches with tomatoes and lettuce; slice fruit onto whole-grain cereal, yogurt, or salads; snack on popcorn; or load up on the vegetable toppings on your pizza.
But beware: Adding too much fiber too quickly can cause gas, bloating, cramps, and diarrhea, so it's better to increase fiber intake gradually. When adding fiber to your diet, make sure to drink extra water, which aids absorption.
An added benefit of eating more fiber is that foods high in fiber also tend to be more nutritious all around, which helps you improve your dietary health overall.
ADA experts recommend that you get most of your dietary fiber from the foods you eat because whole foods also contain vitamins, minerals, and beneficial enzymes. Dietary fiber supplements should play a secondary role; they can be used to boost fiber intake on days you fall short.
