A Dietitian's Advice on Fiber

There are some fibers that may not be that good for you.
- Jane Farrell, BettyConfidential.com

Take a walk down almost any aisle in the supermarket, and you're likely to see the term "Added Fiber" on a lot of packages. Fiber is good, so these products can make you healthier, right?

Maybe not. True, there's no argument about the general benefits of fiber: it can help lower cholesterol ,control blood sugar, and contribute to a feeling of fullness that will make you less likely to eat more food than you need.

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But there are different kinds of fiber, and there's a big difference between them. According to the weight-loss organization TOPS (Taking Off Pounds Sensibly), there's dietary, or intact, fiber (the kind found in naturally existing foods like apples) and added, or isolated, fiber (which is incorporated into manufactured foods). Your total fiber intake is the number of grams of both dietary and added fiber you eat.

These days fiber is being added from everything to ice cream to snack bars, and the labels on the packaging can be confusing. TOPS explains that, for example, a fortified flour tortilla could have close to ten grams of isolated fiber, as opposed to only one gram of intact fiber if no fiber is added.

Katie Clark, assistant clinical professor of nutrition at the University of California, San Francisco, says the benefits of isolated fiber are up for debate. Clark, who is also a nutrition expert for TOPS, explains that it's not certain how much of the benefit derived from total dietary fiber is due to isolated fiber.

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Since there's no concrete evidence of how well isolated fiber performs, she says that "most dietitians and nutrition professionals are recommending that consumers focus on eating foods that are naturally high in fiber." (The American Dietetic Association says further study is needed on the possible benefits of isolated fiber.) The best sources of intact fiber: whole grains; legumes (beans), fresh fruit and vegetables.

Another drawback of isolated fibers is that the foods there are often high in calories and salt. If you're confused at how to find isolated fiber on food packaging, Clark suggests looking for the following terms: maltodextrin; inulin; polydextrose; resistant start; pectin; and gum.

As for how much dietary fiber you're supposed to get each day, the federal recommendation differs depending on your age: 25 grams for women up to 50; 21 grams for women over 50. Clark cautions against trying to up your fiber intake too abruptly; that can lead to gas and bloating. Increase your intake by just a few grams each day, and be sure to drink enough water.

The bottom line: Don't be misled by the mention of fiber on a package. Look at all the ingredients first. Says Clark, "Much like the notion that organic junk food is still food, a high-fiber cookie is still a cookie!"

Jane Farrell is a senior editor at BettyConfidential.

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