Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
15 Feb

Sugar Alcohols: Everything You Need to Know

XylitolI’ve been on a bit of an alternative sweetener kick these past few weeks, for good reason: people want and need to know about this stuff. While a purist shudders at the prospect of any non- or hypo-caloric sugar substitute gracing his or her tongue, I’m a realist. People are going to partake and it’s important to understand what’s entering your body and what, if any, effects it will have. Whether it’s diet soda, artificial sweeteners, stevia, or the mysterious sugar alcohols, people want the sweet without worrying about a big physiological effect – an insulin surge, a blood glucose dip, even a migraine. So I’ve been covering the various types and have tried to be comprehensive about it. As a whole, it all seems fairly safe. Alternative sweeteners might mess with some folks’ adherence to a low-sugar diet, and they might induce or fortify cravings, but the research doesn’t suggest that they’re going to give you cancer or diabetes. The potentially negative effects are all fairly subjective, so it’s safe to play around with them and determine their role in your life based on how they affect your appetite, state-of-mind, and any other subjective health markers.

One remains, however. I have yet to cover sugar alcohols. I was surprised, actually, having gone through my archives and finding nothing. Sugar alcohols are pretty prominent in the low-carb world – all those sugar-free desserts and chocolates and protein bars geared toward Atkins types tend to use sugar alcohols – so I had better get to it, huh?

What Are Sugar Alcohols?

A sugar alcohol, also known as a polyol, is an interesting type of carbohydrate. Its structure is kind of a hybrid between a sugar molecule and an alcohol molecule (hence the name “sugar alcohol”) and, for the most part, our bodies do a poor job of digesting and breaking down sugar alcohol in the small bowel. It’s also sweet to the tongue and resistant to fermentation by oral bacteria, meaning sugar-free gum manufacturers employ it judiciously to sweeten their products without causing cavities. Our colonic bacteria, however, can and do ferment the stuff. For that reason, it’s a kind of prebiotic that, as Kurt Harris points out, can stimulate diarrhea and exacerbate existing irritable bowel syndrome-related symptoms. Common side effects of sugar alcohol consumption (or over-consumption) include bloating, gas, and abdominal pain. Sugar alcohols are not quite non-caloric, but all contribute fewer calories than sucrose, and their effects on insulin and blood sugar (if any) are pretty minimal.

Sugar alcohols pop up in nature, in fruits like apples and pears, but any commercial product that contains them must list the specific alcohols in the ingredients. If they aren’t counted toward the official carb count, they must be listed separately in the nutritional information. Let’s look at some of the popular ones you’ll be encountering:

Xylitol – Glycemic Index of 13

Xylitol is one of the more popular sugar alcohols. It tastes remarkably like sucrose, has about half the calories, and is 1.6 times as sweet, with little effect on blood glucose and none on insulin levels. You can find xylitol in certain berries, corn husks, mushroom fibers, and oats; most commercial xylitol comes from hardwood and corn. Xylitol has a cooling effect on the mouth and is actively protective against dental caries (as opposed to merely being neutral or non-contributive, like the other sugar alcohols), making it the favorite choice of sugar-free chewing gum makers.

There appear to be some interesting health benefits to xylitol, too, beyond the well-established preventive actions against dental plaque and cavities. Xylitol shows promise as a bone remineralization agent, positively affecting both tooth enamel and bone mineral density (albeit, thus far, in rats). I count at least ten studies showing xylitol’s promise in the treatment or prevention of osteoporosis.

Just don’t feed it to your dog. Also, it may exacerbate intestinal distress or cause diarrhea, so exercise caution (and linger near a toilet if you’re unsure of its effect on you).

Sorbitol – Glycemic Index of 9

Sorbitol is found primarily in stone fruits, and manufacturers use it in diet sodas, sugar-free ice creams and desserts, as well as mints, cough syrups, and gum. It’s about half as sweet as sucrose, with 2.6 calories per gram (compared to sucrose’s 4 calories per gram, of course). Being a polyol, it has the potential to cause great gastrointestinal distress, especially in patients with IBS. This is compounded by its relative lack of sweetness when compared to other polyols, like xylitol; people are more likely to consume greater amounts of sorbitol to attain the desired level of sweetness and companies are more likely to use more of it.

There don’t appear to be any proactive beneficial effects with sorbitol. It doesn’t affect insulin or blood glucose, which could be good for diabetics, but there’s nothing like xylitol’s promise.

Erythritol – Glycemic Index of 0

Erythritol is almost non-caloric (0.2 calories per gram) and about 60-70% as sweet as sugar. It’s the only sugar alcohol that doesn’t appear to cause gastrointestinal distress (because the body absorbs it rather than let it pass to the colon for fermentation), it doesn’t affect blood sugar or insulin, and it cannot be fermented by dental bacteria (and it exhibits some of xylitol’s inhibitory effect on carie-causing oral bacteria, though not all of it).

For the most part, erythritol seems pretty safe, and it’s rumored to taste very similar to sugar. Overconsumption – taking in more than your body can absorb – can result in bloating and gastrointestinal distress, but it takes a lot.

Maltitol – Glycemic Index of 36

Maltitol is very similar to actual sugar in terms of mouth feel, taste, and even cooking performance (except for browning, which it cannot do). It’s 90% as sweet with half the calories, so manufacturers love using copious amounts of maltitol in sugar-free desserts and other products. That’s all well and good while you’re eating the stuff, but what about half an hour later once all that sugar alcohol has finally reached your colon and the bacteria has started feasting and fermenting? Bloating, diarrhea, abdominal pain.

It’s right there in the name, isn’t it? Mal.

There are others, but those are the big ones. Overall, the literature shows that sugar alcohols are fairly neutral as far as blood glucose and insulin effects go. Some people may see spikes, as I’ve seen reports on blogs and in comment boards to that effect, but most people won’t. They can hit your gut pretty hard and cause problems there, especially if you’ve got a preexisting condition, but healthy people with healthy digestion (which isn’t as widespread as most people think, of course) should be okay with some here and there. Xylitol in particular seems promising, and I’ll keep my eye out for more information on that as it emerges.

If you’re doing fine without sweeteners (non-caloric, hypo-caloric, artificial, natural, whatever), keep it up. Don’t go looking for an excuse to introduce sugar substitutes. But if your desire for something, anything sweet is derailing your attempts at a healthy diet, sugar alcohols may be worth experimenting with. Give it a shot if you’re gonna and let me know how it goes.

What have your experiences been with sugar alcohols? They get a bad rap from being used in so many processed “low-carb” treats, but have they helped or hindered your path to health? Let me know in the comment section!

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. I ate some small samples of sweets yesterday made with “Swerve” (Erythritol + Chicory) and broke out into hives about an hour later. This morning have some not so fun joint tightness and pain in my hands plus still moderate hives even though I took two doses of Benadryl to try to knock down the allergic reaction. So apparently I am one of the people who has the rare hive reaction to Erythritol.
    For me this supposedly safe sugar alternative is completely not worth it.

    Mika wrote on November 17th, 2013
  2. I have tried to find an answer to the question why ALCOHOL (i.e. wine, whiskey, beer) are “allowed” on the Primal Blueprint eating plan, can anyone answer this for me please? My understanding is that alcohol comes from the sugars?

    Anna wrote on January 3rd, 2014
  3. I just tried the sugar alcohol chocolate mints and man r they good! But I was wondering why I had to stay close to a toilet and now I know. I was having terrible stomach aches and then it hit..lol Thanks for the insight…definitely wont be buying them again!

    Holly wrote on January 15th, 2014
  4. I use xylitol and erythritol for baking at home. (For applications like sweetening drinks where I don’t need the bulk of a sugar alcohol for texture, I just use stevia.) I also buy some maltitol-sweetened ice cream and chocolates. I think they help my long-term low-carb lifestyle more pleasurable. The digestive effects tend to kick in if I have more than 2-3 servings in a day, so they’re pretty easy for me to avoid by staying within my limits.

    Kaylen wrote on February 6th, 2014
  5. i have diabetes type 2 – sugar alcohol spikes my glucose levels significantly. my levels are normally under control but if i have something with even a little bit of sugar alcohol, i can see my readings go up to a number i haven’t seen for a long time. so i don’t know, overall, how it affects others with diabetes, but i’ve learned that for me, it’s best to stay away from it.

    shy wrote on February 13th, 2014
    • Educate yourself. All alcohol sugars are not the same. Some make folks get cramps and diarrhea. Some have a gylcemic number. Erythritol does not. I cannot take the time for your education. The info is out there and Erythritol is great…I use it for everything…get it from an Internet source, 5 # bag is under $30. Very few people I know have had any negative issue with Erthritlol. YOU SHOULD NOT GET A SPIKE WITH IT. IT IS ZERO ON THE GLYEMIC INDEX.BUT you cannot eat breads/chips/rice/corn and other grains…that is what is most likely tipping your blood sugar.

      Cathy wrote on April 8th, 2014
      • i AM educating myself. i was only diagnosed for a couple of months. and cathy – i DO use the internet. there’s a lot of information out there for a new diabetic to ingest. i wasn’t eating any breads/chips/rice/corn – lots of that stuff i cut out right away. i exercise – fit as a fiddle. just genetics are not in my favor. my BG is now very normal. but MOST sugar alcohol will still spike my levels. erythritol is not as bad – but it has a little effect on me as i can not tolerate sugar alcohol very well. not every one is the same so i still go by what i wrote before. it affects people differently. if you educated yourself as you are telling me to, you would know diabetes is not managed exactly the same for everyone. your assumptions that i was dead wrong. i have background studies in nutrition and food science. but that doesn’t mean even i go around assuming i know everything. or that people aren’t educating themselves as you put it. i repeat – there’s a lot of contradicting information out there and new information/research ALWAYS popping up. you would know that if you actually used the internet as much as you claim you do.

        shy wrote on April 9th, 2014
        • So sorry to push your emotional buttons. That is one of the huge problems with typing a note…You could not hear the compassion and understanding in my typing. The only reason I suggested you search the Internet is because I did not have time to type the solution, when I saw your note. You are doing the best you can. Of course, you are. We all do. AND periodically we learn something really amazing. I am a 70 year old holitic registered nurse who speicalizes in nutrition and Energy Medicine. No one has the same body, or the same answers. BUT there is a huge cultural disconnect with what to eat in this country. 99% of the people I know, report that they know they should eat better than they do. Most of those who eat well, do it because they had/have a health issue that forces it. Personnaly I knew what good eating was….but took 65 years to be 100% on board. I ate well for the past 40 years…but not well enough. May your journey be paved with solutions. Sorry about offending you…not at all my intention.

          Cathy wrote on April 9th, 2014
  6. I`m scared about sugar alcohol. I am worried that something bad can happen if i drink milk after i eat a 2g sugar alcohol quaker bar. My dad says that since its only 2 grams, you won`t taste it. Someone please give me advice that its nothing to worry about or that its not the same as normal alcohol.

    Mackenzie Beal wrote on February 16th, 2014
  7. Caramel Turtle Truffle from Baskin-Robbins did a number on my stomach this evening. The bloating, diarrhea and gas I had were the worst I have ever had. it had me running to the restroom every half hour or so. The ice cream was delicious while I was eating it, but now I’m paying the price. Beware of sugar alcohols. :(

    Stacy wrote on March 10th, 2014
  8. I like to buy and consume sugar free chocolate bars from Trader Joe’s, but I was concerned when I found out that one of the ingredients is maltitol, which is made from hydrogenated corn syrup. Since I believe that all corn produced in the U.S. is GMO, I have reason to believe that the corn used to make maltitol is also GMO, and that the hydrogenation of that product makes it an unhealthy food source. Any information about this?

    Kerry Chavez wrote on March 21st, 2014
  9. Sorry guys, Xylitol is metabolized the same way as fructose,i.e. it stimulates visceral fat (de novo lipogenesis)* Seems that since it is a form of powdered alcohol it is metabolized the same way as ethanol(remembering that fructose is fermented into an alcohol too). I can’t seem to find any negatives on Erythritol though. Up to 90% is left unmetabolized and excreted.

    * Effects of xylitol on metabolic parameters and visceral fat accumulation
    Kikuko Amo, et al.
    J Clin Biochem Nutr. Jul 2011; 49(1): 1–7.Published online Jun 17, 2011.
    doi: 10.3164/jcbn.10-111

    Jonathan wrote on May 8th, 2014
  10. Your information on sorbitol is not accurate. It does raise blood sugars, but more slowly and less predictably than sugar because of its tortuous digestion. It provides 2.5 calories per gram (60% the calories of sugar), but is less sweet so often more is used. By the time it gets to the liver it’s fructose, and will contribute to fatty liver and liver insulin resistance. Diabetics, and possibly everybody else, should avoid it at all costs.

    Marshall Wells wrote on June 5th, 2014
  11. Just wanted to say thanks for taking the time to share this information. Very useful stuff!

    Scott wrote on June 24th, 2014
  12. You did not cover monk fruit aka Lo Han. It has finally become available at my local grocery store though I have not looked at it closely. I stumbled across some info about it a few years back, it it was very expensive. Is it a viable alternative? And what about Coconut crystals? I rarely drink coffee, but every other sweetener ruins the taste for me except the Coconut Secret Coconut Crystals (tree sap). What are your opinions on these. I am very new to Primal and even thinking of going Keto first to see if it will help me lose weight. I have many chronic illnesses including Lyme which me being over weight only worsens my situation. At the present time if I use a sweetener I use Xylitol and ofcourse coconut crystals in my occasional cup of coffee (with coconut butter, & raw butter).

    Cissy wrote on July 1st, 2014

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