PERSPECTIVES WITH DR ALAN BARCLAY

SWEET NOTHINGS? 
Consumer demand for reduced sugar, no-added-sugar and sugar free foods and beverages has increased, as people look to cut back on processed foods with added sugars without cutting sweet treats out of their lives. Sugar alcohols or polyols are increasingly replacing them in foods and beverages, often along with intense sweeteners, as they provide similar bulk and texture to sugars but fewer kilojoules/calories. We put together the following table to show you how sugar alcohols compare with added table sugar (sucrose).

A couple of points. While sugar alcohols occur naturally in many plant foods, they are extracted for the food industry from various starches and sugars. You may also notice that the GI values differ from some of the claims you will see on-line and on product packaging. This is because much of the original GI testing was done before ISO 26642:2010 (Food products — Determination of the glycaemic index (GI) and recommendation for food classification) was gazetted in 2010. The ISO sets out how much available carbohydrate each sugar alcohol (polyol)provides and therefore how much is required for GI testing. Prof Tom Wolever has adjusted older GI test results based on the amount of available carbohydrate they contain, and it’s his result we have included.

As they are generally poorly absorbed in our intestines (with the notable exception of erythritol), polyols all provide much less energy than regular sugars. But, with the exception of xylitol, they are not as sweet as sucrose. Therefore, more polyols need to be used to attain the same sweetness in a product, or (more typically), they are blended with an intense sweetener to achieve the same sweetness as sucrose. A very common example is erythritol, which is on average only 70% as sweet as sucrose. It is typically blended with steviol glycosides (“stevia”) to achieve a final product that has a similar bulk, texture and taste as sucrose, that is also “natural”.

Most have a lower GI and all have a lower glycemic load (GL) than sucrose. However, most do provide some available carbohydrate, so if consumed in large amounts, they will have an effect on blood glucose levels – though much less than sucrose.

Finding them in the packaged foods or beverages you buy can be tricky. The good news is that ingredient lists must include the name of individual sugar alcohols/polyols if they are used. The bad news is that they are not a mandatory component of the Nutrition Facts panel in most countries, and therefore are rarely included. The USA is the notable exception where they must be included under Total Carbohydrate when a “sugar free”, “no added sugar” or other sugar claim is made.

Given they are a kind of carbohydrate and excessive consumption can cause wind, bloating and diarrhoea, we think this “invisibility” could be a problem for a significant proportion of the population. It also reminds us that carbohydrates are generally labelled poorly and that it’s not the sugars that are hidden. It’s the sugar alcohols/polyols.

We like the following Nutrition Facts panel for ProYo ice cream and would like to see this approach or something similar widely adopted so people can see what’s sweetening the processed food they buy.

Ingredient list: Skim Milk, Whole Milk, Whey Protein Concentrate, Xylitol (Natural Sweetener), Cane Sugar, Inulin, Natural Flavors, Ground Vanilla Bean

Read more:

• ISO 26642:2010 (Food products — Determination of the glycaemic index (GI) and recommendation for food classification).
• Wolever, T. The glycaemic index: a physiological classification of dietary carbohydrate.
• US FDA. A food labelling guide: guidance for industry. 

Alan Barclay, PhD is a consultant dietitian and chef (Cert III). He worked for Diabetes Australia (NSW) from 1998–2014 . He is author/co-author of more than 30 scientific publications, and author/co-author of  The good Carbs Cookbook (Murdoch Books), Reversing Diabetes (Murdoch Books), The Low GI Diet: Managing Type 2 Diabetes (Hachette Australia) and The Ultimate Guide to Sugars and Sweeteners (The Experiment, New York).

Contact: You can follow him on Twitter or check out his website.