Feedback—Your FAQs Answered

Which sweeteners can be used to support the low GI diet and have no calories?
Check out the ‘What Sweetener Is That?’ table in The New Glucose Revolution for Diabetes (US/Canadian edition) or The Diabetes and Pre-diabetes Handbook (ANZ edition). It will give you the GI and calories per gram of a wide range of nutritive and non-nutritive sweeteners plus brand names and the per teaspoon equivalent of table sugar if you want to substitute. Here’s a summary.

Non-nutritive sweeteners (such as Equal®, Splenda®, NutraSweet® or saccharin) are all much sweeter than table sugar and have essentially no effect on your blood glucose levels because most are used in such small quantities and are either not absorbed into or metabolised by the body. Because they are only used in minute amounts, the number of calories they provide is insignificant. The best non-nutritive sweeteners to cook with are Splenda®, saccharin and Neotame®, and to a lesser extent Equal Spoonful®. This is because the non-nutritive sweeteners made of protein molecules often break down when heated for long periods and lose their sweetness.

Nutritive sweeteners including sugars, sugar-alcohols, and oligosaccharides (medium-sized chains of glucose) are simply different types of carbohydrate with varying levels of sweetness. The sugar alcohols like sorbitol, mannitol and maltitol are generally not as sweet as table sugar, provide fewer calories and have less of an impact on blood glucose levels. To overcome their lack of sweetness, food manufacturers usually combine them with non-nutritive sweeteners to help keep the calorie-count down and minimise the effect on blood glucose levels so check the ingredient listing on the food label.

I read that Diet Coke and Diet Sprite have a high GI. Why is that, as they contain only artificial sweetener?
Diet soft drinks made with alternative sweeteners contain so little carbohydrate their GI can’t be tested – it is negligible. So we wouldn’t trust any source that tells you they have a high GI. Regular Coca-Cola tested following the standardised international method has a low GI (53) as does regular Schweppes lemonade (GI 54). Regular Fanta has a medium GI (68).

Which products can be used to thicken sauces or soups? Arrowroot?
We are often asked about the GI of starchy thickeners from arrowroot and cornstarch, to kudzu root powder and instant tapioca and covered it all in some detail in GI News in August 2006. None of these thickeners has been GI tested as far as we know. You usually use only very small amounts of these thickeners (a teaspoon or two) so the GI of the recipe will depend more on the other carb ingredients in what you are making rather than the thickener. However, here are our alternative ideas for thickening soups. For vegetable soups, puree some of the cooked vegetables then stir them back into the soup to thicken. Adding grated starchy vegetables like sweet potato or yams will also thicken a vegetable soup; or stale, well-crumbled breadcrumbs (sourdough or grainy of course) to a mushroom soup. For a creamy soup you can stir in a little light evaporated milk or low fat yoghurt. Pureed cooked or canned white beans will also thicken a vegetable soup. If readers have some other good ideas, we’d be glad to add them to the list.

I read about Prof Jennie Brand-Miller’s study, ‘Effect of alcoholic beverages on postprandial glycemia and insulinemia in lean, young, healthy adults.’ Can you explain what substances in white wine contribute to lower glucose response and how this works?
Here’s what Jennie says: ‘Alcohol itself is a major reason why white wine lowers the glucose response. It is well known that the alcohol reduces the production of glucose molecules by the liver. If we drink too much, we can be ‘hypoglycemic’ (low blood sugars) in the morning. But it’s also possible that there are other components at work. Wine is acidic and we know that acidic substances such as malic acid (which is also known as fruit acid), will slow down stomach emptying.’

Prof Jennie Brand-Miller