Sugar Alcohols

xylitol, erythritol, maltitol, mannitol, sorbitol, lactitol, isomalt, hydrogenated starch hydrolysates

When I first started this website, I included xylitol as a natural sweetner. But then I changed my mind. Here's why.

Sugar alcohols (also called "polyols") are a family of sweetening agents considered to be food additives. Not food, food additives. They are regulated by the Food and Drug Administration as either GRAS (Generally Recognized As Safe) or approved food additives. They have no nutritive value.

Sugar alcohols are neither sugars nor alcohols. They have a chemical structure that partially resembles sugar and partially resembles alcohol, but they are not alcohols like wine or whiskey.

Sugar alcohols do occur naturally in small amounts in fruits and vegetables--including mushrooms, lettuce, berries, apples, and plums--but for commercial purposes, they are manufactured from carbohydrates such as sucrose, glucose, and starch.

So are they natural sweeteners? I would have to say no. They don't occur in nature in any appreciable amount that can be collected. There is no sugar alcohol hive or tree or plant. The amount that nature has provided in fruits and vegetables is miniscule, and in the context of lots of water and fiber in other nutrients. Though they are made through a natural fermentation process, it is a manufactured product--you can't go collect sugar alcohols in nature somewhere and use them as a sweetener.

To isolate only the sugar alcohols, manufacture them in a factory, and add them to other foods takes them out of natural balance. The purpose of sugar alcohols is to reduce the caloric value of manufactured food products. Indeed, of all the sugar alcohols, only two are widely available to home cooks.

In addition, our bodies don't recognize them as food. Once ingested, sugar alcohols are slowly and incompletely absorbed from the small intestine into the blood, then converted to energy by processes that require little or no insulin. About half is not absorbed into the blood. This passes through the small intestine into the large instestine, where it is fermented by bacteria, producing abdominal gas and discomfort. It can also have a laxative effect or cause diarrhea. While this may seem inconsequential, over and over in studying about food and food additives, I find that manufactured food products thought to be safe and even advertised as "healthy" often turn out to have long-term health effects that cannot be initially observed.

Sugar alcohols are not acted upon by bacteria in the mouth, and therefore do not cause tooth decay. Because xylitol has even been found to inhibit oral bacteria, it is used in sugarless mints and chewing gums for this reason. This is a health benefit, however, oral bacteria can be reduced in other ways.

Sugar alcohols have been promoted as acceptable sugar substitutes for diabetics. Unlike other sweeteners that cause a quick rise in blood sugar, sugar alcohols do not produce significant changes in blood sugar because, once absorbed, they are converted to energy by processes that require little or no insulin. After reading this, I considered xylitol to be an "unlimited" acceptable sweetener, only to find out after eating as much xylitol-sweetened fudge that I wanted for a week that it did elevate my blood sugar, which came right back down when I stopped eating xylitol.

Name of Sugar Alcohol % Relative Sweetness to Sucrose Calorie Value kcal/g Derived From

Mannitol 50 - 70 1.6 Fructose

Sorbitol 50 - 70 2.6 Glucose

Sorbitol Syrup 25 - 50 3 Corn, Wheat or Potato Starch

Xylitol 100 3 D-xylose

Maltitol 90 3 High Maltose Corn Syrup

Maltitol Syrup 25 - 50 3 Corn, Wheat or Potato Starch

Lactitol 30 - 40 2 Lactose

Isomalt 45 - 65 2 Sucrose

Erythritol 60 - 80 0.2 Glucose

Polydextrose 0 1 Dextrose (Glucose), Sorbitol & Citric or Phosphoric Acid

In addition to the fact that sugar alcohols do not occur in nature as a food, and they don't metabolize completely in our bodies, I just don't like the taste of sugar alcohols. They don't give me the sweet satisfaction of the traditional whole food sweeteners. I'd much rather have a small portion of something sweetened with honey or evaporated cane juice and have the "real thing" rather than the strange taste (strange to me) of a sugar alcohol.

And they are difficult to work with. They are most useful to sweeten beverages or other liquids, like smoothies or salad dressings. They don't act like sugar in baking. They won't crisp or brown. They also have a minty "cooling effect" which limits the flavors it can be used with.

To be fair, I feel I need to also tell you that sugar alcohols have been used since the 1960s in foods such as chewing gum, gum drops and hard candy, and in pharmaceuticals and oral health products such as throat lozenges, cough syrups, children's chewable multivitamins, toothpastes and mouthwashes. The safety of xylitol, specifically, has been proven in long-term clinical studies. It is approved as a sweetener in more than 35 countries. The World Health Organization and the FDA have given xylitol their safest ratings for food additives. Babies and small children can use it without restriction.

You decide for yourself if you want to use sugar alcohols. For myself, I've decided against them.

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After writing the above, I found more about sugar alcohols.

In the book, The 7 Principles of Fat Burning: Get Healthy, Lose Weight and Keep It Off!, Dr. Eric Berg writes:

Artificial sweeteners, which are in thousands of foods, cause water retention...These include...sugar alcohols, such as...xyotol or mannitol...I initially did recommend sugar alcohols as acceptable sweeteners but with more of my own research found that they are big water retainers, so I don't recommend them any more.

A low-carb website has this to say about sugar alcohols:

Most of these "low carb" products are sweetened with substances called "sugar alcohols." Maltitol, lacitol, and sorbitol are some of names of these sweeteners. Despite the name, these aren't sugars or alcohols. They are hydrogenated starch molecules which are a byproduct of grain processing.
These sugar alcohols are manufactured by the three large agribusiness companies: SPI Polyols, Roquette America, Inc. and Archer Daniels Midland. Having saturated world with high fructose corn syrup, these giant corn-producing companies have now turned to hydrogenated corn starch molecules as yet another way to wring profits out of surplus corn.
Despite wrapper claims, these sugar alcohols are metabolized. Each gram of a sugar alcohol turns into anywhere from less than 1 to as much as 3 calories. Erythritol comes in lowest, delivering less than one calorie per gram. Maltitol--the sugar alcohol found in most "low carb" foods is the highest, delivering 3 calories per gram. That is only a bit less than 4 calories you find in regular sugar and starch.
It is because these sugar alcohols can be metabolized as carbohydrates that US law requires that they be reported as carbohydrates on nutritional labels and why their calories are included in calorie counts...
Small print on back of these label explains that fiber and sugar alcohols have a "negligible effect on blood sugar". This, they suggest means that you can ignore them, and magically converts foods that have 24 grams of carbs--and the associated calories--into foods with a diet-friendly 3 grams.
If it were true that these foods did not raise blood sugar, it would make them ideal for the low carb diet. However, it is not always true. Some lucky people can eat these low carb treats and still lose weight on a low carb diet. But hundreds of people who have stopped by the alt.support.diet.low-carb news group to ask why their weight loss has stopped cold, discover that it is these sugar alcohol-laden low carb junk foods that have caused their long-term stalls.
The reason for this, is quite simply, that sugar alcohols, particularly Maltitol, the one that is most common in these products, can have a very significant impact on blood sugar. This isn't speculation. It's a fact. Many people with diabetes, who track any rise in their blood sugar with a blood sugar meter, find that these products cause a significant rise in their blood sugar, contrary to the label claims.
I'm one of them [and I'm one of them, too -Debra]. My blood sugar rises almost as high when I eat a maltitol-sweetened Russell Stover "No Sugar" candy as it does if I eat a regular Russell Stover candy of same size. The only difference is that it takes two hours for the blood sugar rise to occur when I eat the "no sugar" candy compared to the one hour that it takes when I eat regular candy. So much for "truth in labeling."
I am not only person who has found this to be true. Fran McCullough warns readers of the very high blood sugar spikes reported by diabetics after eating glycerine-containing Atkins bars in her book, Living Low Carb.
A comprehensive review published by the Canadian Journal of Diabetes gives a very good overview of the scientific research into how sugar alcohols affect both normal people and people with diabetes.
Sugar Alcohols and Diabetes: A Review
Note the finding, on Page 5, that research shows that chocolate bars sweetened with maltitol raised the blood sugar of normal people as high as did chocolate bars sweetened with sucrose--table sugar.
However, there are other people with diabetes who report that they don't see a blood sugar rise when they eat foods containing these sugar alcohols. They find these products give them a way to incorporate legitimate treats into their diets and are grateful that they are now so plentiful.
There are also a number of successful low carbers who report in diet newsgroup that they have been able to lose significant amounts of weight while including these "low carb" treats in their food plans on a daily basis. You will often find them railing against "puritanism" of those who warn new dieters against them.
So, clearly these products do not affect everyone in same way. For some people they are a godsend. For others, they turn out to be "Stall in a Box."
Since it seems that only a subset of the population metabolizes sugar alcohols as sugar, it is quite possible that some people lack some enzyme(s) needed to digest them and turn them into blood sugar. Since those people's bodies can't turn these sugar alcohols into glucose, they do not experience a blood sugar rise when they eat them.
Lending some support to this idea is fact that some of the people who report that they did not experience a blood sugar rise when they ate a product with a sugar alcohol in it, add that they experienced intense diarrhea or gas later on. These are classic symptoms of what happens when starches pass undigested into lower gut where they may be fermented by bacteria (causing gas) or suck water out of cells lining the colon (causing diarrhea).
Many of us who do get blood sugar rise do not experience this diarrhea. Our digestive enzymes appear to be able to break down these hydrogenated starches into glucose--though given the time lag, this happens slowly.
Diabetes expert Rick Mendosa has a very interesting web page at http://www.mendosa.com/netcarbs.htm that points out "If the sugar alcohols had no impact on our blood glucose, they would have a glycemic index of zero.
With the the December 2003 publication of Geoffrey Livesey's amazing review of sugar alcohols, we now know a lot more about them than ever before. Mendosa cites the article, "Health potential of polyols as sugar replacers, with emphasis on low glycemic properties in Nutrition Research Reviews 2003;16:163-91.
Mendosa goes on to say: "Only two of the sugar alcohols have a GI of zero, according to Livesey's research. These are mannitol and erythritol. Several others have a very low GI, but two maltitol syrups have a GI greater than 50. This is a higher GI value than that of spaghetti, orange juice, or carrots."

International Food Information Council: Sugar Alcohols Fact Sheet

Health Canada: Sugar Alcohols (Polyols) & Polydextrose used as Sweeteners in foods

NOTE: XYLITOL CAN BE DANGEROUS TO DOGS. While xylitol causes very little effect on blood sugar in humans, when ingested by dogs it can cause a dangerous surge of insulin. In as little as 15 minutes, there can be a marked drop in blood sugar. It only takes a little and the window for treatment is very short. Ingestion can be fatal. Xylotol can also cause severe liver damage within 24 hours. (enter "xylitol dogs" into your favorite search engine for more information)