1 August 2006

Feedback—Your FAQs Answered

What is the law in relation to making a low GI claim on a product in Australia? I have noticed all sorts of claims on various products and seen brands that use a symbol similar to the official GI symbol. I think that this could be rather misleading to shoppers.
Alan Barclay of Diabetes Australia gets asked about this regularly. Here’s what he wrote in a recent issue of ‘Conquest’.

Claims about the GI of foods are currently not regulated under Australian food law. Manufacturers are free to make claims provided they are not false or misleading. They should print the GI value of the food on the food label, to help you to verify the claim. A food with a low GI should have a value less than or equal to 55. There are a number of brands that make low GI claims but do not provide a GI value or definition of what low GI means on the label. Unfortunately, you have no way of verifying whether the claim is legitimate. To do so you’d need to be carrying around the latest version of The Shopper’s Guide, have a mobile phone (call one of Diabetes Australia's dietitians on 1300 136 588) or have internet access through your mobile phone (check the GI database at www.glycemicindex.com). Without verification, it’s probably sensible not to trust the claim because you have no idea whether the food was tested following the standardised procedure by an accredited lab.

You may also see products claiming to be ‘low glycemic’ or ‘diabetic friendly’ leaving it open as to whether it’s low GI, low GL, or low glycemic response. Be cautious with these claims as the product could actually be low carb (check the nutrition label). Manufacturers making these claims may not be intending to mislead the consumer, they simply may not understand the difference. It’s useful to write and ask what they mean and where the food was tested. There are a number of foods that use low GI logos that are similar to the Glycemic Index Tested logo. Some of these cases have been pursued through legal channels.

  • Consumers in Australia or New Zealand who have concerns about GI label claims, should contact FSANZ and/or the Australian Competition and Consumer Commission (ACCC).
  • Consumers in the USA and Canada can contact the Food and Drug Administration's Office of Compliance at the Center for Food Safety and Applied Nutrition (for USA) and the Canadian Food Inspection Agency (for Canada).
And remember when it comes to reading labels, GI is only part of the picture –don't forget to check the nutrition panel for the fat, salt, and kilojoule/calorie content per serving.

Alan Barclay

The GI Symbol Program: This international symbol is a guarantee that the product meets strict nutritional criteria. Glycemic Index Limited is a non-profit company established to run the GI Symbol Program. Its members are: the University of Sydney, Diabetes Australia and the Juvenile Diabetes Research Foundation. For more information, visit www.gisymbol.com.


I work third shift, four days a week from 2100 to 0600–0700. Sometimes I eat before I go to bed and other times I skip it. When I get up I eat the main meal of the day at 1700–1800 and leave for work shortly after. I have a 15-minute break every two hours and an hour lunch break at 0200 am when I usually eat yoghurt. I have put on weight although I haven’t changed my eating habits. I just don’t know when, how, and what to eat.
Shift work can be a problem, especially for people with diabetes says dietitian Kaye Foster-Powell. Like anyone else who needs to get rid of excess weight, it’s important to talk to a dietitian about total daily food requirements and where and how meals, snacks and activity could be distributed over the day/night. She says that there are a couple of key points that can help shift workers shift excess weight.

The first is sleep. There are studies that show that just small amounts of less sleep than needed (as little as 20 minutes) are associated with weight gain. Here at GI News we aren’t experts on how disrupting the body’s normal circadian rhythm affects biological systems, but weight gain could be simply a consequence of inadequate sleep – 6–7 hours sleep is less than normally recommended for most people.

Secondly, having some structure to meals and snacks also helps. So for someone on third shift, for example, a main at 1700–1800 hours, a snack at 2300 hours, lunch at 0200 and breakfast at 0700–0800 hours would be a useful starting point.

In addition, new research by Medical Research Council scientists at the MRC Laboratory of Molecular Biology in the UK and published in Current Biology has found a major clue to why shift workers suffer from increased incidence of heart disease and metabolic illnesses. The daily ‘body clock’ determines which enzymes are produced by the liver at which time of day and night. This means that the liver’s ability to process meals follows a regular daily progression. Dr Michael Hastings, who led the research, explains: ‘When our body clocks are disturbed (by shift work or jet lag) so as to cause a mismatch between when and what we eat and what the body is able to process at meal times, nutrients are handled less effectively, for example fats will not be cleared from the blood stream and blood sugar levels will not be regulated appropriately.’
– Medical Research Council Press Release
Current Biology, Vol 16, 1107-1115, 06 June 2006

Kaye Foster-Powell

What’s the GI of a Caffé Latte and Cappuccino?
Most milky drinks will have a low GI and won’t add too many kilojoules/calories either so long as you don’t sweeten them with more than a teaspoon or so of sugar and you say no to those flavoured syrups lined up on the counter. In fact a caffé latte, cappuccino, café au lait or flat white can be the perfect mid-morning snack and an easy way to help you get your two to three serves of dairy foods a day. Regular or skim, milk has a low GI (27–34) – a combination of the moderate glycemic effect of its sugar (lactose) plus milk protein, which forms a soft curd in the stomach and slows down stomach emptying. Regular whole milk is high in saturated fat, but these days there’s a wide range of reduced fat milks including low fat and skim types. If you prefer soy milk (GI 36–45 reduced fat) make sure you opt for calcium fortified and of course, reduced fat. Note that rice milk is not a suitable substitute; it has a high GI (79). How much milk are you getting with your coffee? Well, to some extent it depends on the barista and where you buy it. But here are some standard definitions.
  • A caffe latte is a single shot of espresso with steamed milk – approximately a 3:1 ratio of milk to coffee.
  • A cafe au lait is similar except it is generally made with brewed coffee instead of espresso in a ratio of 1:1 milk to coffee.
  • Cappuccino is traditionally equal parts espresso, steamed milk and frothed milk.
  • Flat white is similar to a cappuccino, but with latte proportions of foam.

What’s the GI of cornstarch?
We are often asked about the GI of starchy thickeners from arrowroot and cornstarch, to kudzu root powder and instant tapioca. These silky powders thicken sauces and soups and pie fillings without adding fat or going lumpy. All you do is mix about a teaspoon of the starch into a tablespoon of water, whisk into the liquid you are thickening, and cook for about a minute, stirring constantly to remove the slightly starchy flavour. These proportions will make about 1 cup (250 ml) of a medium-thick sauce. None of these thickeners has been GI tested as far as we know; we haven’t seen any published results. However, you are only using very small amounts diluted in a cup or more of liquid or pie filling. So the GI of the recipe will depend really on what you are making. However, here are some alternative ideas for thickening sauces and soups.

Sauces: Simply reducing the sauce will thicken it and intensify the flavour.
Soups: For vegetable soups, puree some of the cooked vegetables then stir them back into the soup to thicken. Added 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.

In June GI News in the piece on toppings (‘Test Is Best’) you seemed to say that eating fat reduces the GI of a food (and thus would seem to be a good thing). In Feedback in the same issue you seem to say that eating a fat does not reduce the need for insulin and thus presumably does not help one. What’s the story?
It can be confusing. Here are the facts, one at a time.
  1. Eating any carbohydrate raises blood glucose and insulin levels.
  2. Adding fat or replacing some of the carbohydrate with fat will reduce the glycemic response.
  3. But the insulin response is unchanged.
  4. We don't want people to lower blood glucose values by adding saturated fats (cheese, butter etc) because that increases the risk of cardiovascular disease. It's much more helpful to choose a low GI carbohydrate food!
  5. We don't want people to lower blood glucose values by adding excessive amounts of ANY fat (saturated or unsaturated) because that increases energy intake and compromises weight control. That's not to say that we should avoid good fats, it's a matter a moderation.
  6. Mixed meals containing a mix of protein, fat and carbohydrate tend to have a lower GI than single high carbohydrate foods like bread and rice.
  7. The glycemic and insulin response to mixed meals can be nicely predicted by (1) the total carbohydrate content of the meal and (2) the GI of the component carbohydrate foods.
  8. The usual cut-offs for high, medium and low GI (70, 56 to 69, less than 55) are meant for single high-carbohydrate foods, not mixed meals. Because the range of GI will be narrower for mixed meals, a different set of cut-offs need to be developed. We won't know what those cut-offs should be until we've tested dozens of mixed meals. With the increasing trend to test the GI of ‘meal replacements’, that may not be far off.
The bottom line: In the meantime, our advice is to choose lean proteins, good fats (unsaturated), plenty of fruit and vegetables and good carbs (low GI wholegrains) in the proportions you enjoy. If you are trying to lose weight, control the portion sizes and get a total of 60 minutes of incidental and deliberate activity each day.


Look it up in our A–Z: The GI Glossary (continued)
Ketones Our bodies need to maintain a minimum threshold level of glucose in the blood to provide energy for our brain and central nervous system. If for some reason, glucose levels fall below this threshold, (a very rare state called hypoglycemia) the brain will make use of ketones – a by-product of the breakdown of the body’s fat stores. Ketones are strong acids, and when they are produced in large quantities they can upset the body’s delicate acid-base balance. They are normally released into the urine, but if levels are very high or if the person is dehydrated, they may begin to build up in the blood. High blood levels of ketones may cause fruity-smelling breath, loss of appetite, nausea or vomiting, and fast, deep breathing. In severe cases, it may lead to coma and death. In a pregnant woman, even a moderate amount of ketones in the blood may harm the baby and impair brain development. Large amounts of ketones in the urine may signal diabetic ketoacidosis, a dangerous condition that is caused by very high blood glucose levels.

Ketosis is the metabolic state when the body is burning fat for fuel. Normally carbohydrates are the main source of fuel for your brain, heart and many other organs.

Kilojoule or kJ is the metric system for measuring the amount of energy produced when food is completely metabolised in the body. The Calorie is the imperial measure of energy, and can be calculated from the number of kilojoules by dividing by 4.2.

Lipids or fats are found in the blood and the walls of all of the body’s cells. The most common lipids are cholesterol and triglycerides (sometimes called triacylglycerols).

LDL cholesterol see Cholesterol

Millimole (mmole) is a unit for measuring the concentration of glucose, cholesterol, triglycerides and other substances in a certain volume of blood – usually 1 litre (L).
Mono-unsaturated fat is found in large quantities in olive and canola oil, and some nuts and seeds. Like all fats, mono-unsaturated fats are high in kilojoules. Mono-unsaturated help lower LDL cholesterol levels and are thought to help reduce the risk of heart attack and stroke.


Anonymous said...

Excellent info on coffee! The information on milk, soy milk and rice milk was very helpful. What is the glycemic index of lactose-free milk?

Anonymous said...

The lactose free 'milks' tested to date are soy milk and rice milk. The reduced fat soy beverages enriched with calcium have a GI ranging from 36-45 depending on the brand. But all are low GI. The only rice beverage tested had a high GI - 79.