Net Carb Nuances: Fiber and Sugar Alcohols

There are nuances to fiber and sugar alcohols that make a simple net carb calculation inaccurate. For an overview of net carbs and how to use their information to boost health, don’t miss the post Food Label Insight: What Are Net Carbs?

Fiber Facts:

The FDA definition for dietary fiber on a food label includes both naturally occurring fibers in foods as well as added isolated or synthetic non-digestible soluble and insoluble carbohydrates that have beneficial effects on our health. These effects include lowering blood sugar and cholesterol levels, reduced calorie intake, and increasing the frequency of bowel movements. Fiber is only naturally present in plants: vegetables, grains, fruit, and legumes. Food processing often removes fiber – think about the difference between white bread (fiber removed) and whole wheat bread (fiber from wheat included). 

The FDA has identified the following isolated or synthetic non-digestible carbohydrates that meet the dietary fiber definition:

• Beta-glucan soluble fiber

• Psyllium husk

• Cellulose

• Guar gum

• Pectin

• Locust bean gum

• Hydroxypropylmethylcellulose

You’ll also find a wide range of additional types of fiber listed in the ingredients as food manufacturers look for ways to boost the fiber content of foods. It’s not determined if these additional types of fiber provide the same health benefits as the fiber that is naturally present in foods, which include:

• 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)

Polyol Facts:

There are different types of polyols, including erythritol, hydrogenated starch hydrolysates (sometimes listed as maltitol syrup, hydrogenated glucose syrup, polyglycitol syrup, polyglucitol or simply “HSH”), isomalt, lactitol, maltitol, mannitol, sorbitol and xylitol.

Per FDA regulations, the name of the specific polyol may appear on the Nutrition Facts label if only one polyol is in the food. If more than one polyol is in the food, you’ll see the term “sugar alcohols.”

The individual polyols used in a food must be included in the ingredients list on a food label.

References:

1. Food Consulting Company. Food Labelers Beware:  Carbohydrate Labeling is Tricky. https://www.foodlabels.com/press-release-carbohydrate-claims published 3-1-2004; accessed 12-20-22

2. WebMD. When a Carb’s Not A Carb: The Net Carb Debate. https://www.webmd.com/women/features/net-carb-debate  accessed 12-20-22

3. Atkins. What are Net Carbs? https://www.atkins.com/how-it-works/library/articles/what-are-net-carbs  accessed 12-20-22

4. Monash University. What are Polyols? https://www.monashfodmap.com/blog/what-are-polyols/ posted 4-17-16; accessed 12-20-22

5. U.S. Food and Drug Administration. Questions and Answers on Dietary Fiber. https://www.fda.gov/food/food-labeling-nutrition/questions-and-answers-dietary-fiber#define_dietary_fiber  Updated 12-17-21; Accessed 12-20-22

6. Calorie Control Council. Polyols. https://polyols.org/about-polyols/  Accessed 12-20-22