FAQs About Polyols
Today’s Dietitian
By Hope S. Warshaw, MMSc, RD, CDE
Vol. 6 No. 4 p. 36

Today, there are more calorie- and nutrition-conscious consumers than ever before. Their desire for foods and beverages with fewer calories and less sugars and fats is fueling a growth in the availability of these foods. The increased number of foods marketed toward nutrition-conscious consumers is also due to the availability of a greater number of improved ingredients that assist manufacturers in developing these foods. According to the Calorie Control Council’s 2000 survey, 180 million Americans consume these foods.1

Polyols are a group of carbohydrate-based ingredients used in increasing amounts in sugar-free, reduced-sugar, and low-glycemic foods. Because consumers are using these foods in increasing numbers, nutrition professionals should understand what polyols are, what foods they are used in, and how to advise clients to use these foods to achieve their nutrition and health goals. This article provides answers to these questions.

Q: What are polyols?
A: Polyols are a group of low-digestible carbohydrates that provide a range of calories per gram—from 0.2 to 3. The calories per gram accepted by the FDA for each polyol are noted in Table 1 in order of increasing caloric density.2 The approximate average calories per gram is 2, compared with 4 calories per gram from most other sources of carbohydrate. Many people know polyols as sugar alcohols. The preferred name is polyols because they are neither sugar nor alcohol.

Q: What foods are polyols used in?
A: Polyols are used in an array of food products, including chewing gum, candy, ice cream, baked goods, chocolate, and fruit spread. They are also used in toothpaste, mouthwash, breath mints, and pharmaceuticals such as cough syrups, cough drops, and throat lozenges.

Q: Why do food manufacturers use polyols?
A: Food manufacturers use polyols to replace sugars and/or fat to produce foods that are lower in calories, sugar, and/or fat. Polyols provide bulk to products such as low-fat, reduced sugar, and/or no-sugar-added baked goods, frozen dairy desserts, sauces, and salad dressings. Beyond sweetening, polyols are used for other functional benefits, such as those listed in Table 2.

Q: How are polyols being used today in the food supply?
A: The way polyols are used today is evolving. Prior to the 1980s, polyols were solely found in so-called diabetic and dietetic foods, which were centralized in a small section of supermarkets. Sorbitol was the only polyol available at that time, so the variety of products was restricted. Today, a variety of polyols with different technological properties is available. This new variety of ingredients enables food manufacturers to produce quality foods with great taste and nutritional advantages. Thus, today, foods made with polyols are dispersed throughout the supermarket. These foods may contain one or several polyols or contain one or more polyols in combination with one or more no-calorie sweeteners, such as acesulfame-K, aspartame, saccharin, or sucralose.

Q: How are polyols digested and metabolized?
A: Polyols, like fiber, provide fewer calories per gram than other carbohydrates. This is because they are slowly and incompletely absorbed from the small intestine. The portion of polyols that is absorbed is metabolized by processes that require a minimal amount or no insulin. The portion that is not absorbed into the blood is broken down into smaller segments in the large intestine.

Due to the incomplete absorption, a large amount of polyols consumed at one time may cause gastrointestinal effects, such as gas or laxative effects similar to reactions to beans and certain high-fiber foods. The severity of the symptoms depends on the individual, amount of the food that is consumed in one time, type of polyol, and existence of any prior period of adaptation.

Gastrointestinal symptoms, if they occur, are usually mild and transient. If people believe they are sensitive to polyols, they may want to reduce the amount of the product they eat at one sitting. It is worth noting that if a person incorrectly believes these products are calorie- or carbohydrate-free, they may eat large amounts. This is why it is important to review with clients during nutrition assessments the use of these foods and amount they eat at one time. Most people will adapt to the mild gastrointestinal effects within a few days, just as they adapt over time to the initiation of a high-fiber diet.

The FDA is aware of the potential laxative effect of polyols. Therefore, they require the following informational food label statement on foods whose daily consumption may result in 50 grams of sorbitol or 20 grams of mannitol: “Excess consumption may have a laxative effect.” See Figure 1 for an example.

Q: Can foods sweetened with polyols produce a lower rise in blood glucose after consumption?
A: Due to the slower and incomplete absorption of polyols, they result in a lower blood glucose rise after consumption. All polyols have a low glycemic index.3 As such, they can serve a role in reducing the overall glycemic load. However, though the American Diabetes Association agrees that polyols produce a lower postprandial rise in blood glucose response than monosaccharides or disaccharides, they believe there is no evidence to date to indicate that the amount of polyols likely to be consumed in a meal or throughout a day would result in a significant reduction in total daily energy intake or to improve long-term glycemic control.4 Nonetheless, in weight control, every calorie counts.

Q: How are polyols regulated by the FDA?
A: Most polyols in use today are in a category of ingredients referred to as GRAS—Generally Recognized as Safe. When Congress passed the 1958 Food Additives Amendment of the Food, Drug, and Cosmetic Act, two important groups of substances were exempted from the FDA’s food additive definition. Those exempted are (a) substances GRAS among experts qualified by scientific training and experience to evaluate safety and (b) substances that either the FDA or the U.S. Department of Agriculture (USDA) had sanctioned for use in foods prior to 1958 (so-called prior sanction substances). General recognition of safety based on scientific procedures calls for the same quantity and quality of scientific evidence that is required to obtain a food additive approval. If a petition is submitted to the FDA for GRAS affirmation, once the petition is accepted for filing, the substance may be legally used for the petitioned uses.5

In April 1997, the FDA proposed a replacement for the GRAS system called the GRAS notification system. This system is currently being used, although the FDA has not finalized the regulation. Using this system, manufacturers may still make a self-determination of GRAS. However, instead of petitioning the FDA for affirmation, manufacturers notify the FDA of their GRAS determination and provide evidence supporting their decision.5

Food additives are defined as substances that have previously not been part of the U.S. food supply. Food manufacturers must determine a food additive’s safety, submit a petition for specific uses, and have the food additive approved for use by the FDA prior to its use in the food supply.5

Erythritol, hydrogenated starch hydrolysates,6 isomalt,7 lactitol,8 maltitol,9 and sorbitol10 are considered GRAS. Mannitol has interim food additive status,11 and xylitol12 is a food additive approved for special dietary purposes.

Q: What are the food labeling regulations about polyols?
A: Figure 1, “Guide to FDA Food Labeling Regulations for Polyols,” provides the essential regulations in coordination with a Nutrition Facts label.13 This figure will be beneficial for nutrition professionals as well as for use with clients.

Q: Some companies that manufacture foods containing polyols are using wording on their products such as “net carbs” or “impact carbs.” Are these nutrition claims allowed by the FDA or USDA? What do the manufacturers mean to communicate to consumers with the use of these phrases?
A: The food manufacturers using these terms appear to subtract the total grams of polyols and fiber from the grams of total carbohydrate in the product. The remaining or zero grams of carbohydrate are then referred to as net carbs. The wording encourages counting only these grams of carbohydrate as they are the only ones, as stated, to have an impact on blood glucose. Note, the terms and wording varies from label to label.

It is important to note that this information appears outside of the Nutrition Facts panel. Though these terms have been introduced over the last two years, there has been no regulatory or policy change from the FDA indicating that the food labeling regulations that define total carbohydrate, sugars, sugar alcohols (as noted in Figure 1), and several other sources of carbohydrate have changed.13 The Food Safety and Inspection Service of the USDA, which has jurisdiction over meat and poultry products, has issued a Statement of Interim Policy of Carbohydrate Labeling. Practitioners are encouraged to review the complete statement.14 In essence, the USDA states that it will “not object to terms such as ‘Net Carbs,’ ‘Effective Carbs,’ and ‘Net Impact Carbs’ when used in a manner that is truthful and not misleading.”

As part of this new calculation, manufacturers provide a statement to indicate that only the net carbs in the product have an impact on blood glucose. They do not make a statement about calories. Thus, the people whom these new terms are a concern for are people with diabetes, especially those who use insulin. Clearly, for people who do intensive diabetes management and take rapid-acting insulin to cover carbs using the net carb information vs. the guidelines provided later in this article (How can nutrition professionals teach people how to fit these foods into their eating plans?) could cause a person to underestimate his or her insulin need. This could lead to a higher blood glucose level several hours later, without an understandable explanation. This is both confusing and a safety concern.

For people who are more concerned with counting grams of carbohydrate and/or calories, it means that if they use the net carbs, they will not have a correct count of their carbohydrate or calorie intake. For people without diabetes or prediabetes, their blood glucose levels are regulated by a sufficient amount and normal regulation of insulin.

A recent answer in the “Question of the Month” column in The Journal of the American Dietetic Association elucidates this area further and encourages consumers to continue at this time to count polyols in foods as described later in this article.15

Q: What is the relationship between polyols and the reduced risk of tooth decay?
A: Polyols are not readily converted to acids by bacteria in the mouth. Therefore, they do not promote tooth decay. In 1996, the FDA authorized the use of a health claim related to sugar alcohols and dental caries. According to the 1996 rule, foods that are “sugar-free” according to the FDA’s definition and contain the polyols erythritol (added in 1997), hydrogenated starch hydrolysates, hydrogenated glucose syrups, isomalt, lactitol, maltitol, mannitol, sorbitol, xylitol, or a combination of these may be labeled with a health claim such as “Frequent between-meal consumption of foods high in sugars and starches promotes tooth decay. The sugar alcohols in [name of food] do not promote tooth decay.”16 A sample shortened claim is, “Does not promote tooth decay.” In July 2003, the FDA published a final rule permitting a “does not promote tooth decay” health claim for products sweetened with D-tagatose, a novel sugar. Products containing D-tagatose may not, however, be labeled “sugar-free.”16

Q: What should nutrition educators be teaching people with diabetes about polyols?
A: Too often, people with diabetes believe the most important nutrient to eliminate from their food intake is sugar. This is due to the now-outdated advice about avoiding sugars and sweets.4 People with diabetes often purchase “sugar-free” foods without an understanding of the ingredients, foods, and how to fit these foods into their eating plans. This is unfortunately due to a lack of or a very limited amount of diabetes self-management training (DSMT) and/or medical nutrition therapy (MNT).

When providing DSMT and/or MNT, educators should make the following points about polyols17:
· The nutrition claim “sugar-free” does not necessarily mean calorie- or carbohydrate-free. Sugar-free simply means that the food does not contain any one- and two-unit sugars (monosaccharides and disaccharides).
· Identify the names of polyols so they will be able to identify these ingredients on the ingredient list. Teach the rule of thumb that most, but not all, polyols end in “ol.”
· Foods with the nutrition claim “sugar-free,” “no sugar added,” or “no added sugars” can vary in their calorie and carbohydrate counts and ingredients. They may be sweetened with one or more polyols, one or more no-calorie sweeteners, or a combination of polyols and no-calorie sweeteners.
· Beyond the sweetening ingredients (which may or may not contain carbohydrates and calories), these foods may contain calories and nutrients from other ingredients (eg, cookies, yogurt, or hot cocoa) or not (diet soda or other diet drinks). Have product labels available to show examples of the various scenarios.
· Foods sweetened with polyols may contain other calorie-containing ingredients that may raise blood glucose.
· The Nutrition Facts label and the ingredient list should be used to determine how to fit sugar-free foods into eating plans according to the guidelines provided later in this article. (How can nutrition professionals teach people how to fit these foods into their eating plans?)

Q: What should nutrition educators be teaching people interested in weight management about polyols?
A: People attempting to achieve weight loss and long-term weight maintenance should learn most of the points noted in the previous answer. However, the most important point is the caloric content of the foods.

Q: How can nutrition professionals teach people how to fit these foods into their eating plans?
A: Teach people to use the following guidelines.18 Use the Nutrition Facts labels and ingredient lists from specific foods a client uses or have the labels of commonly used “sugar-free” foods available.

1. If all the carbohydrate in the food is from polyols and the total carbohydrates is less than 10 grams, consider it a “free food.” Limit servings to three or less per day. This is because if all the carbohydrate is from polyols, there are less than 5 grams of total carbohydrate (polyols on average contain 2 calories per gram) per serving. Less than 5 grams of carbohydrate per serving can be counted as a free food according to the Exchange Lists for Meal Planning.19

2. If all the carbohydrate in the food is from polyols and the grams of polyols are greater than 10, then subtract one-half the grams of polyols from the total carbohydrate grams. Count the remaining carbohydrate grams into the eating plan using Table 3.

Example (refer to Figure 2):
31 grams of polyols ÷ 2 = 16
36 grams of total carbohydrate – 16 (1/2 grams of polyols) = 20 grams of carbohydrate to count. Count as 20 grams of carbohydrate or 1 carbohydrate choice.

Note: If the calories are calculated based on 4 calories per gram, the total would be 144. Because 31 grams of the total carbohydrate can be calculated (by the manufacturer) at an average of 2 calories per gram, the calories per serving are approximately 80.

3. If there are several sources of carbohydrate in the food, including polyols, then subtract one-half the grams of polyols from the total carbohydrate grams. Count the remaining grams of carbohydrate using the chart below.
Example (refer to Figure 3):
16 grams polyols ÷ 2 = 8
21 grams of total carbohydrate – 8 (1/2 grams of polyols) = 13 grams of carbohydrate to count. Count as 13 grams of carbohydrate or 1 carbohydrate choice.

— Hope S. Warshaw, MMSc, RD, CDE, has authored a number of professional publications and five best-selling consumer nutrition and diabetes books, including Diabetes Meal Planning Made Easy (American Diabetes Association, 2000) and Eat Out, Eat Right! (Surrey Books, 2003). The author received an honorarium by the Calorie Control Council for the preparation of this article for Today’s Dietitian.

References for this article are available upon request by e-mailing TDeditor@gvpub.com.

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