Sugar Alcohols: Help or Hoax?

What do you do with sugar alcohols when reading labels? A very good question.   I've had countless patients enter my office cussing at some "sugar-free" chocolate bar that shot their sugars through the roof. And recently a reader asked the same question - it's time to address it.

Sugar alcohols like xylitol and sorbitol are not "alcohol" in the way we know it. They are sweeteners and carbohydrates - but with less calories than sugar. They are sometimes called polyols. And yes, they can still affect blood sugar and weight- although to a lesser extent. . . err, sometimes. Here are the "buts" . .  .

The Bad Points to Sugar Alcohols

1. They are sometimes included as carbohydrate on the label.

2. They are sometimes not included under carbohydrate on the label, but still listed elsewhere on the label. (Like the 4 g net carb ice-cream bar someone at Costco tried to sell me a box of. They each had almost 20 grams of sorbitol. I could get another lower carb product for half the price - oh, and less calories, less fat and less gas!) 

3. They are not "free" - Half the grams of sugar alcohols are counted as carbohydrate (should you be carb counting)>

4. Some sorbitol etc. products have just as many calories (or more) than the normal product.

5. Products using significant amounts of sorbitol, maltitol etc. versus sugar (sucrose) don't have the same texture as real "sugar" products so often compensate by increasing the fat content to get a better "mouth feel". 

6. More than 10 g of these sweetners may cause gas, bloating, cramps or even diarrhea. The smaller the person, the less they can tolerate so be careful or kids can cramp easily.

7. "Sugar free" products  with these sweetener alcohols can lead people to unknowingly eat more of these products and suffer higher blood sugars. Bugger. (FYI :  "Sugar Free" means "sucrose" or white-table-sugar free.)

8. The flip side, if these sweetners are counted as part of the total carbohydrate of a product and you give insulin for it because you're carb counting, you might get a low blood sugar (as only half of sorbitol, xylitol etc. is converted to calories and quite slowly). 

9. Portions sizes can be deceiving. These products - like any product -can often have labels that are for 1/3 or 1/2 of what you think is a normal portion size. I recall an expensive Callebaut chocolate bar (very high end wonderful stuff folks - and real chocolate) having less calories, less fat and equal carb compared to the "sugar free" variety that a representative once tried to  push at our diabetes centre. She was showing us the analysis based on 1/2 the bar. Us dietitians aren't dumb. We multiplied it out and of course included half the grams of sorbitol as being carbohydrate. In the end, we saw real no benefit for our patients to buy this over regular chocolate. Especially after some of us suffered in bathroom after eating the samples!

10. Products with significant amounts of sugar alcohols are usually more expensive.

11. They don't usually taste as good as the "normal" product. But, this is subjective.

12. A WARNING: People taking orlistat or XenicalŽ acarbose or PrandaseŽ may experience severe gastric discomfort when eating sugar alcohols.

The Good Points to Sugar Alcohols

1. Sugar alcohols do cause less of a rise in blood sugar compared to sugar,  for most people. (If the amount of the food is limited. ) However, most normal chocolate is also low glycemic index in smaller amounts- meaning slow to raise blood sugars too. Again, the problem is usually portion. 

2. Sugar alcohols don't promote cavities.  In fact, xylitol can inhibit some oral bacteria - so you often see it in sugar-free gum. Granted in small amounts. A very beneficial additive in this product.

3. Hmmm. . . I'm thinking. . . still thinking. Ah well, something will come to me later.

Carb Counting: Sorbitol, Xylitol and other Sugar Alcohols

Having named the "buts" I'm still a big big fan of personal choice. If you are looking to include these products into your diabetes diet,  are carb counting or just want to be label savvy, here's how according to both the Canadian and American Diabetes Associations.  

Half the grams of sugar alcohol are counted as carb.

If sugar alcohol is included under carbohydrates, then subtract half of the grams of sugar alcohol from the carbohydrate like in the following example. (PS. Always remember to subtract grams of fibre from the carbs since fibre is a indigestible carbohydrate. PPS. For your reference, a piece of bread is 15 grams of carb.)

Sugar alcohol included under the carbohydrate heading.

If these alcohols are NOT included under carbohydrates, then add half of their grams to the carbohydrate. 

Sugar alcohol NOT included under the carbohydrate heading.

Want more detail?

Although sugar alcohols are poorly absorbed in the bowel (or not at all in some cases) they are digested by bacteria that take up residence in our colons. More accurately put, these sweeteners are fermented by the bacteria. The resulting by-products are absorbed by us and do give us energy or calories (technically kcal) - oh, and there are the by-products of gas that can leave us bloated or with diarrhea. For your interest:

**via fermentation by bacteria and absorption as short chain fatty acids
Canadian Journal of Diabetes: Volume 26 Number 4; pp 356-362

As a diabetes educator and dietitian I of course promote moderation, whether it be with "sugar free" sugar alcohol products or with the regular sugar sweetened products. You decide which is best for you,  your pocketbook, or your taste buds. And of course, do check your blood sugars as everyone is different and you simply won't know the effects of food products without the blood sugar monitoring.

www.diabetes. ca (Canadian Diabetes Assoc.)
www.diabetes. org (American Diabetes Assoc.)
Wolever et al., CJD 26(4):356-362, 2002.
www.healthcanada. ca/nutritionlabelling
Armit E and the NNC, CDA. Report from the NNC. Diabetes Quarterly. 2003 (1):14
National Nutrition Committee, Canadian Diabetes Association. Guidelines for Assigning Food Choice Values and Symbols Beta Release 1993: 17 (3) p.11-15
Armit E and the NNC, CDA. Report from the NNC. Diabetes Quarterly. 2003 (1):14

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