Questions and Answers on Dietary Fiber
Resources
- What is FDA's definition for dietary fiber that can be declared on the Nutrition and Supplement Facts labels?
- What are some of the actions that FDA has taken on dietary fiber?
- What are some examples of a physiological effect that is beneficial to human health that would have to be demonstrated before FDA would propose to allow the added isolated or synthetic non-digestible carbohydrate in a food product to be declared on the label as a dietary fiber?
- What are examples of naturally occurring fibers?
- What isolated or synthetic fibers have FDA included in its dietary fiber definition?
- Until FDA engages in rulemaking, how will the additional dietary fibers that FDA intends to propose to be added to the definition of dietary fiber be handled by FDA?
Manufacturer-Specific Questions
- What if a manufacturer wants to declare as “dietary fiber” on the Nutrition and Supplement Facts labels a non-digestible carbohydrate that is not intrinsic and intact and that is not one of the dietary fibers in the current definition?
- How do manufacturers know how much dietary fiber to declare on the Nutrition and Supplement Facts labels and how should this be documented?
- What was the deadline for manufacturers to modify product labeling if a product contains added isolated or synthetic non-digestible carbohydrates that do not meet the definition of dietary fiber?
- If a manufacturer has submitted a citizen petition, but FDA has not yet responded, can the manufacturer include the amount of the added isolated or synthetic non-digestible carbohydrate that is the subject of the petition in the “dietary fiber” declaration in the meantime?
General Questions
What is FDA's definition for dietary fiber that can be declared on the Nutrition and Supplement Facts labels?
Dietary fiber that can be declared on the Nutrition and Supplement Facts labels includes certain naturally occurring fibers that are “intrinsic and intact” in plants, and added isolated or synthetic non-digestible soluble and insoluble carbohydrates that FDA has determined have beneficial physiological effects to human health. These effects include lowering blood glucose and blood cholesterol, reducing calorie intake, and increasing the frequency of bowel movements.
The Nutrition Facts label final rule defines “dietary fiber,” in relevant part, as “non-digestible soluble and insoluble carbohydrates (with 3 or more monomeric units), and lignin that are intrinsic and intact in plants; isolated or synthetic non-digestible carbohydrates (with 3 or more monomeric units) determined by FDA to have physiological effects that are beneficial to human health.”
What are some of the actions that FDA has taken on dietary fiber?
December 2021: FDA added "acacia (gum arabic)" to the existing list of isolated or synthetic non-digestible carbohydrates that FDA intends to propose to be added to the definition of dietary fiber.
January 2020: FDA added “glucomannan” to the existing list of isolated or synthetic non-digestible carbohydrates that FDA intends to propose to be added to the definition of dietary fiber.
March 2019: FDA added “cross-linked phosphorylated RS4” to the existing list of isolated or synthetic non-digestible carbohydrates that FDA intends to propose to be added to the definition of dietary fiber.
June 2018: The agency responded to and granted many of the citizen petitions it received requesting that the agency consider adding certain isolated or synthetic non-digestible carbohydrates to the list of those that meet the regulatory definition of "dietary fiber." In addition, FDA issued a guidance and released a science review to identify eight isolated or synthetic non-digestible carbohydrates (NDCs) that the agency intends to propose to be added to our regulatory definition of "dietary fiber." The guidance expresses FDA's intent, pending rulemaking regarding adding additional fibers to the "dietary fiber" definition, to exercise enforcement discretion if manufacturers include the eight recognized fibers when calculating the amount of dietary fiber to declare on the Nutrition and Supplement Facts labels, and for the use of a caloric value for polydextrose of 1 kcal/g.
February 2018: FDA released a final guidance about how FDA intends to evaluate the scientific evidence submitted as part of these citizen petitions.
November 2016: FDA released a draft guidance for industry: “Scientific Evaluation of the Evidence on Beneficial Physiological Effects of Isolated or Synthetic Non-Digestible Carbohydrates Submitted as a Citizen Petition,” to address the type of evidence that should be provided as part of a citizen petition requesting that an isolated or synthetic non-digestible carbohydrate be included in the dietary fiber definition and the approach we plan to use to evaluate the evidence.
November 2016: FDA published a request for scientific data, information, and comments to help us to determine whether certain isolated or synthetic non-digestible carbohydrates should be added to our definition of "dietary fiber." We noted that manufacturers may submit to FDA a citizen petition that provides scientific evidence of a beneficial physiological effect of the isolated or synthetic non-digestible carbohydrate to human health.
May 27, 2016: FDA announced the Nutrition and Supplement Facts label final rule, which included a definition of "dietary fiber," and identified seven isolated or synthetic non-digestible carbohydrates as meeting the dietary fiber definition.
What are some examples of a physiological effect that is beneficial to human health that would have to be demonstrated before FDA would propose to allow the added isolated or synthetic non-digestible carbohydrate in a food product to be declared on the label as a dietary fiber?
Examples of physiological effects that are beneficial to human health include:
- Lowering postprandial blood glucose and/or insulin
- Lowering fasting LDL-cholesterol or fasting blood glucose
- Lowering blood pressure
- Increased frequency of bowel movements (improved laxation)
- Increased mineral absorption in the intestinal tract
- Reduced energy intake
What are examples of naturally occurring fibers?
Naturally occurring fiber (often referred to as "intrinsic") occurs in foods such as vegetables, whole grains, fruits, cereal bran, flaked cereal and flours. The fibers are also considered to be "intact" because they have not been removed from the food. Foods containing these fibers have been shown to be beneficial, and manufacturers do not need to demonstrate that they provide beneficial physiological effects to human health. We have issued guidance for the scientific evaluation of isolated or synthetic non-digestible carbohydrates, which are added to food, to evaluate whether the carbohydrate has a beneficial physiological effect to human health and, consequently, meets the definition of "dietary fiber."
What isolated or synthetic fibers have FDA included in its dietary fiber definition?
In addition to intact and intrinsic fibers, FDA has identified the following isolated or synthetic non-digestible carbohydrates as meeting the dietary fiber definition:
- Beta-glucan soluble fiber (as described in §101.81 (c)(2)(ii)(A))
- Psyllium husk (as described in §101.81 (c)(2)(ii)(B)(1))
- Cellulose
- Guar gum
- Pectin
- Locust bean gum
- Hydroxypropylmethylcellulose
Further, based on FDA's review of the science, FDA intends to propose that the following non-digestible carbohydrates be added to the definition of dietary fiber:
- Mixed plant cell wall fibers (a broad category that includes fibers like sugar cane fiber and apple fiber, among many others)
- Arabinoxylan
- Alginate
- Inulin and inulin-type fructans
- High amylose starch (resistant starch 2)
- Galactooligosaccharide
- Polydextrose
- Resistant maltodextrin/dextrin
- Cross linked phosphorylated RS4
- Glucomannan
- Acacia (gum arabic)
Until FDA engages in rulemaking, how will the additional dietary fibers that FDA intends to propose to be added to the definition of dietary fiber be handled by FDA?
Until FDA completes rulemaking regarding adding additional fibers to the regulatory definition of dietary fiber, the agency intends to exercise enforcement discretion to allow manufacturers to include the amount of these additional fibers in the dietary fiber declaration on the Nutrition and Supplement Facts labels.
Manufacturer-Specific Questions
What if a manufacturer wants to declare as “dietary fiber” on the Nutrition and Supplement Facts labels a non-digestible carbohydrate that is not intrinsic and intact and that is not one of the dietary fibers in the current definition?
The manufacturer may submit a citizen petition for FDA’s consideration that provides scientific evidence of a beneficial physiological effect to human health. Also, if an added isolated or synthetic non-digestible carbohydrate is the subject of an authorized health claim that FDA evaluated using the health claim petition process in 21 CFR 101.70, FDA would consider the non-digestible carbohydrate to meet the definition of “dietary fiber” and would propose to amend the definition accordingly.
In Appendix A of FDA’s June 2018 guidance, “The Declaration of Certain Isolated or Synthetic Non-Digestible Carbohydrates as Dietary Fiber on Nutrition and Supplement Facts Labels: Guidance for Industry,” FDA addresses the degree to which a non-digestible carbohydrate can be isolated or synthesized from its original plant source, but still be considered intrinsic and intact.
How do manufacturers know how much dietary fiber to declare on the Nutrition and Supplement Facts labels and how should this be documented?
The amount of dietary fibers declared should represent the total fiber that is quantified by analytical methods minus the amount that does not meet the dietary fiber definition. Analytical methods cannot distinguish between non-digestible carbohydrates that do and do not meet the dietary fiber definition. Therefore, firms must keep records for those foods that contain both non-digestible carbohydrates that do meet the regulatory definition of dietary fiber and added non-digestible carbohydrates that do not meet the definition of dietary fiber.
What was the deadline for manufacturers to modify product labeling if a product contains added isolated or synthetic non-digestible carbohydrates that do not meet the definition of dietary fiber?
FDA issued a final rule to extend the compliance dates for the Nutrition Facts and Supplement Facts label final rule and the Serving Size final rule from July 26, 2018, to Jan. 1, 2020, for manufacturers with $10 million or more in annual food sales. Manufacturers with less than $10 million in annual food sales had an extra year to comply—until Jan. 1, 2021.
If a manufacturer has submitted a citizen petition, but FDA has not yet responded, can the manufacturer include the amount of the added isolated or synthetic non-digestible carbohydrate that is the subject of the petition in the “dietary fiber” declaration in the meantime?
A manufacturer cannot include isolated or synthetic non-digestible carbohydrates that are the subject of pending petitions in the declaration of “dietary fiber.” However, the added carbohydrate must be included in the declaration for total carbohydrate.