GI News—August 2006

In This Issue:

• Food for Thought
  —A high carb diet: is it still the ideal public health message?
  
• GI News Briefs
  —Carb quality, weight loss and heart health
  —Keeping the kilos off
  —High GI carbs linked to oxidative stress
  —Spice notes: Cinnamon; Chilli
  —High GI diets and fatty liver disease
  
• GI Values Updates
  —The latest GI values from SUGiRS
  
• Low GI Food of the Month
  —Split peas – more than a winter warmer
  
• Low GI Recipe of the Month
  —Split Pea, Watercress and Goat’s Curd Salad
  
• Success Stories
  —Bedrich: Little changes – Big difference
  —David Lee Nall says: ‘Taking care of yourself is the best way to take care of others.’
  
• What's New?
  —The Low GI Diet, revised and updated Australian and New Zealand edition
  
• Feedback—Your FAQs Answered
  
  1. What is the law in relation to making a low GI claim in Australia?
     
  2. I work third shift, four days a week, and I have noticed that in the past couple of years I have put on weight although I haven’t changed my eating habits. Can you help me get this excess weight off?
     
  3. What’s the GI of a caffe latte and cappuccino?
     
  4. What’s the GI of cornstarch?
     
  5. What’s the story about fat, the GI and your insulin response?
  6. Look it up in our A–Z: The GI Glossary (continued)
     

GI News Editor: Philippa Sandall
Web Design and Management: Scott Dickinson

Food for Thought

A high carb diet: is it still the ideal public health message?
The proportion of people with excess body fat has doubled in the last two decades despite all our efforts to slim down. Between half and two-thirds of adults in developed nations are classed as overweight or obese. Men are worse off than women, and our children are affected, too – approximately one in four weigh much more than they should for their age and height. Even our pets are suffering – over quarter of all cats and dogs are classed as overweight and many have diabetes as a result. The food industry has met our demand for ‘diet’ and ‘lite’ foods, low fat foods, sugar substitutes, fat substitutes – you name it, they made it. But this has not stemmed the obesity epidemic. Indeed, some experts feel the food industry and its advertising are partly to blame.

Millions of people around the world are following carbohydrate-modified diets for weight loss as well as general health. And certainly both high protein and low GI diets have caught the public’s attention if diet book sales are anything to go by. With obesity and diabetes reaching epidemic proportions, what’s the best way to lose weight?

Earlier this year, the results of the largest weight loss study ever carried out indicated that a low fat dietary intervention was not a magic bullet for preventing weight regain (JAMA 2006; 295: 39). In contrast, recent studies published in JAMA, The Lancet, American Journal of Clinical Nutrition, American Journal of Epidemiology and International Journal of Obesity, suggest low GI diets have specific beneficial effects over and above that of the conventional low fat diet. But not all studies have been consistent. Are some individuals more likely to see benefits of low GI diets than others? How do high protein diets compare with those that focus on carbohydrate quality, ie. the GI?

Explore the question of carb quantity or quality with some of the world’s leading researchers at a one-day forum in Sydney on September 2 including:

• Prof Jennie Brand Miller from the University of Sydney
• Prof Arne Astrup, Royal Veterinary and Agricultural University, Denmark
• Associate Professor Frank Hu, from Harvard University
• Dr William Yancy from Duke University, USA
• Dr Manny Noakes from the CSIRO, Adelaide
• Dr Anette Buyken from Forschungsinstitut für Kinderernährung in Germany
• Dr Emma Stevenson (or Prof. Clyde Williams) from Nottingham University

Professor Jennie Brand-Miller

‘Carbohydrates, the Glycemic Index and Health’
Click HERE for registration or more information

GI News Briefs

Carb quality, weight loss and heart health

With the obesity epidemic a front-page story, ‘diet wars’ is a hot topic. And at the centre of the debate is the quantity and quality of carbohydrate. What should it be: low carb or slow carbs? The findings of a study by researchers from the University of Sydney’s Human Nutrition Unit and published in July Archives of Internal Medicine clearly show that carb quality really counts for weight loss and heart health. Led by Joanna McMillan-Price, the research team carried out the world’s first 12-week, parallel, randomised, controlled trial to compare systematically the relative effect on weight loss and cardiovascular risk of four low GI and high protein diets. Both high protein and low GI diets will help you shed fat they found, but a diet rich in low GI carbs will also significantly reduce your risk of heart disease.

Speaking to GI News, Joanna McMillan-Price said that: ‘While high protein and low GI diets may seem to be diametrically opposed, they in fact will both reduce glycemic load. That is they both reduce your blood glucose and insulin levels. This fits with what we know about our hunter/gatherer ancestors. Although they ate large amounts of meat when it was available, they also ate large amounts of plant foods (leaves, berries, nuts, seeds) which would have been gathered every day ensuring that their diet was naturally low GI and low GL. And of course whether hunting or gathering, they would have been much more active than we are today.’
– Archives of Internal Medicine 2006; 166:1466–1475


Joanna McMillan-Price

GI Group: So what’s the take home message? First of all, one diet doesn’t have to fit all: What’s important is that you set yourself attainable goals and your diet is one you enjoy and can live with over the longer term. If it involves a lot of sacrifice and discipline on your part (eg no sugar or carbs of any sort), it’s bound to fail sooner or later. Our tips:
Step 1: Focus on reducing saturated fat and eating the good fats instead.
Step 2: Choose low GI smart carbs to maximise body fat loss as well as cardio benefits.
Step 3: Aim to eat at least five serves of vegetables and two serves of fruit every day (preferably of three or more colours) including leafy greens, beans and peas, salad vegetables, pears, apples, oranges etc.
And be active. Get those legs, not the fingers, to do the walking.

Editorial comment from Dr Simin Liu, Department of Epidemiology, UCLA:
‘What should physicians do differently based on the findings of this new study? My best recommendation is to move forward incrementally. For example, as a first step, we should encourage the use of GI and GL concepts in conjunction with caloric density and nutrient composition, especially for ranking high-carbohydrate starchy foods, since the classification of carbohydrates incorporating GI does work better than the “simple vs complex” classification for predicting glucose and insulin responses …. In more practical terms, we need to teach our patients to identify low-GI foods within different food groups … Without any drastic change in regular dietary habits, for example, one can simply replace high-GI grains with low-GI grains and starchy vegetables with less starchy ones and cut down on soft drinks that are often poor in nutrients yet high in GL’
– Archives of Internal Medicine 2006; 166:1438–39


Dr Simin Liu

Keeping the kilos off
People on diets high in slowly digested carbohydrate and low in saturated fat can successfully lose weight and keep it off finds a study presented at the Australian Institute of Food Science and Technology Incorporated Convention in July. University of Melbourne research dietitian Liz Delbridge and her team put 173 overweight or obese people on a 12-week low-energy weight loss diet before switching them randomly to either a high carbohydrate or high protein diet (low–moderate GI carbohydrate choices were recommended for both diets) to maintain their weight. Results showed that a high protein diet had no advantages over a high carbohydrate diet in maintaining weight loss over a 12-month period. ‘Some people lose weight and keep it off, whereas others lose weight and put it all back on again,’ said Ms Delbridge. ‘We wanted to see if the type of diet people adopted after weight loss had an influence on people’s ability to keep the weight off.’
– Australian Institute of Food Science and Technology Incorporated Convention

High GI carbs linked to oxidative stress
We have all received the message that it’s important to eat plenty of anti-oxidant rich fruit and vegetables to fight the bad guys, those free radicals (see below) that have been implicated in the cause of numerous diseases. Free radicals are formed in the environment by things like pollution, cigarette smoke, solvents and pesticides; and in the body as a byproduct of metabolism, wherever oxygen is involved. Recent research has suggested that high blood glucose may also increase free radical production. In a report published in American Journal of Clinical Nutrition, lead author Gladys Block says that ‘increasing intakes of low GI foods such as most fruit, vegetables, dairy products and whole grains may be beneficial in terms of reduced oxidative stress.’ The researchers measured plasma MDA and IsoP concentrations (two widely used markers of oxidative stress – see below) in 292 healthy individuals and found a direct relationship between dietary GI and oxidative stress. In their conclusion they say that: ‘Chronic consumption of high GI foods may lead to chronically high oxidative stress. A low GI diet, not a low carbohydrate diet, appears to be beneficial in reducing oxidative stress.
– American Journal of Clinical Nutrition 2006;84:70–6

GI Group
A free radical is an atom or molecule with at least one unpaired electron, making it especially reactive to other atoms or groups of atoms. If free radicals react with certain chemicals in the body, they may interfere with the ability of cells to function normally.
Oxidative stress is related to the body's ability to eliminate free radicals and can result in cell damage within the body.

Spice notes
Herbs and spices bring more than fragrance and flavour to our food. Research in recent years suggests that some spices such as turmeric, garlic, ginger and cinnamon and chilli may have healthy benefits for our digestion, blood glucose control, fat metabolism and for fighting free radicals.

Cinnamon: Two promising studies report that as little as the equivalent of ¼ teaspoon of cinnamon daily may improve blood glucose control. In the earlier Diabetes Care (Vol 26, pp3215–18) study, Dr Alam Khan from the NWFP Agricultural University in Peshawar, Pakistan gave 60 diabetic men and women between 1 and 6 grams of cinnamon or a wheat flour placebo each day for 20 days. Those who took cinnamon showed significant improvements in blood glucose, LDL cholesterol and triglyceride levels. More recently, researchers from the University of Hannover led by B. Man randomly 79 diabetic volunteers a cinnamon solution (in a capsule) equal to 1 gram of cinnamon or a placebo each day. After four months fasting blood glucose levels improved in the cinnamon group by an average of 1.1 mmol/L (European Journal of Clinical Investigation Vol 36, pp340–44). The GI Group looks forward to seeing some spicy follow up research on cinnamon with controls for overall diet and physical activity levels.



Chilli: Research in recent years has provided some evidence that capsaicin, the chemical that gives chilli peppers their bite, can raise your metabolic rate. But the studies have tended to be small, or used supplements rather than the real thing and certainly not definitive. Hot off the press from the American Journal of Clinical Nutrition (2006;84:63–9) comes news that will be popular with spice lovers; a meal containing freshly chopped chilli may help reduce insulin levels. Kiran Ahuja and researchers from the University of Tasmania’s School of Life Sciences compared the effects of a chilli meal after four weeks of eating bland (spice-free) meals and a chilli meal after four weeks of spicy meals, with eating a bland meal after four weeks of bland meals. In their randomised, crossover intervention study with 36 participants, they found that eating a chilli meal reduced the amount of insulin required to bring down postprandial blood glucose levels. Their results also suggested that the effect is likely to be more pronounced in individuals with a greater BMI (equal to or greater than 26) and when chilli was regularly eaten. Medscape members can read further information on this study at www.medscape.com.


photo: Scott Dickinson

High GI diets and fatty liver disease
As the incidence of obesity in adults and children increases, so does non-alcoholic fatty liver disease (NAFL) – excess fat in the liver. It is strongly associated with insulin resistance and relatively common in people with type 2 diabetes. Currently there are no effective treatments other than weight loss, which makes the findings of a new Italian study published in the American Journal of Clinical Nutrition timely. Valtueña and colleagues suggest that a low GI diet may help people with NAFL more than low carb or high fibre diets and be a complementary tool for preventing or treating it. In their cross sectional study of 247 healthy individuals, the researchers looked at dietary correlations with NAFL assessing the effects of both the quality and quantity of carbohydrate. They found that the GI of the diet is a good marker for fatty liver. The higher the GI, the greater the prevalence of fatty liver, especially in insulin resistant people. In an editorial in the same issue, Prof David Jenkins calls for further studies to ‘assess whether a low-GI diet, given as an intervention, makes a difference in the natural history of NAFL.’
– American Journal of Clinical Nutrition 2006;84:136-42
– American Journal of Clinical Nutrition 2006;84:3-4 (Editorial)

GI Values Update

The latest GI values from SUGiRS

Beans, Peas and Legumes
Casa Fiesta Refried Beans, GI 38

Beverages – Milk
Pura Light Start, GI 30
Pura Tone, GI 30
Pura HiLo, GI 20
Pura Skimmer, GI 20
Big M Chocolate flavoured milk, GI 37
Big M Strawberry flavoured milk, GI 37

Bread
Bakers Delight Wholemeal Country Grain, GI 53



For details of nominal serve sizes, available carbohydrate and GL check out the GI database at www.glycemicindex.com

For more information about GI testing at Sydney University, please contact:
Fiona Atkinson sugirs@mmb.usyd.edu.au
Research Manager, Sydney University Glycemic Index Research Service (SUGiRS).
Human Nutrition Unit, Department of Biochemistry (GO8)
Sydney University, NSW 2006 Australia


Fiona Atkinson

Low GI Food of the Month

Split Peas: More Than a Winter Warmer
Like other low GI legumes (pulses), protein-rich split peas are a nutritional storehouse. They are an excellent source of fibre, vitamin C, along with some iron, zinc and B group vitamins. When you cook them, they more than double in weight and when you eat them, you’ll feel satisfied for longer. You don’t need to soak them before cooking, but rinse them thoroughly in a colander first. Yellow or green split peas (GI 32) come from a variety of garden pea with the husk removed. They tend to disintegrate when cooked for long periods and are associated with comfort foods like pea and ham soup and (yellow split peas) for Indian dhal or to make patties and purees. But they can be more than a winter warmer. You can also use them for fairly fast food for summery salads, too as you’ll discover in the following recipe.

Low GI Recipe of the Month

Split Pea, Watercress and Goat’s Curd Salad
This salad created by Kate Tait for June 2006 Delicious magazine is a deliciously complete meal in itself and can be prepared, cooked and served in around 30 minutes.


Kate Tait - photo by Petrina Tinslay

You can buy ready roasted capsicum and goat’s curd cheese from delis, gourmet food shops and larger supermarkets.

1 cup (200 g) green split peas
1 tablespoon olive oil
Juice of 1 lemon
2 teaspoons ground coriander
½ teaspoon ground ginger
1 red onion, very finely chopped
1 bunch watercress, stalks trimmed (to give 3 cups sprigs)
2 roasted red capsicums, cut into strips
¼ cup goat’s curd or soft goat’s cheese

Cook the split peas in a saucepan of boiling water for 15–18 minutes until tender, but firm to the bite. Meanwhile, make the dressing by placing the oil, lemon juice, spices and onion in a large bowl and whisking until combined. Drain the peas well and add to the dressing. Season to taste if desired and toss to combine. Stand for 10 minutes to let the flavours absorb then toss with the watercress sprigs and capsicum strips. Divide evenly among four plates and top with goat’s curd.

Per serving: Energy: 1155 kJ/276 Cal; Protein: 17 g; Carbohydrate: 28 g; Fibre: 7.6 g; Fat: 8.8 g (includes saturated fat 2.4 g)

Your Success Stories

Bedrich: Little changes – Big difference
‘For 15 years I ran my own small company in Prague. During those 15 years I spent a lot of time driving or sitting at a desk, developing software applications and seeing clients. Many times I would miss meals and I would end up eating on the run or I would miss meals completely and have a huge meal late at night. The result was my weight soared from 76 kg when the company began to a peak of 97 kg during 2005. My energy levels were not good, I felt unhealthy, and worse, a blood glucose test in 2004 showed that my 2-hour blood glucose levels were too high. Both my mother and father had type 2 diabetes and, at 55, I knew I needed to make some changes but didn't know how or where to begin.

Everything changed for me when I visited my daughter in Australia for 3 months in late 2005. She told me about the GI and the importance of daily exercise. I began eating oats with fresh fruit for breakfast and for lunches I would make my own sandwiches using capeseed rolls, salad and a cheese slice. I used avocado instead of butter. We always had a salad with dinner that contained different beans and vegetables. We typically ate poached chicken breast or tinned fish but would also have lean cut steaks on a BBQ. Another major change was daily walking to and from the bus or train station. When I left in late February 2006, my weight had dropped to 82 kg. Best of all I just felt so much better.

Today back in Prague my weight is 84 kg nearly four months later. I continue to choose low GI carbohydrates in place of the old high GI versions I ate before Australia and am now walking to the train station to get to work leaving the car behind. I am confident I will be able to maintain my new weight with these new but easy changes.’



David Lee Nall says: ‘Taking care of yourself is the best way to take care of others.’
‘I was living the American dream: I had a beautiful family, a new house, four cars, and a business that was grossing seven figures. I had come a long way for a skinny, dyslexic kid who had been a poor student. But in the midst of all this hard-earned success, my weight had climbed to 245 pounds, my energy levels were flagging, and I discovered some tumors on my stomach and lower back. Although the tumors were diagnosed as benign, the health scare was a wake-up call. I wasn’t even 30 years old. My son was only four. I wanted to be around to see him grow up.

On 1 December 2004, I decided to change my life once and for all. I made the decision to start taking care of myself. I bought healthy foods, watched what I ate, and restructured my exercise routine. And I resolved to enter the 2006 Texas Shredder Classic, a natural, drug-tested, body building contest.
I began eating small, frequent meals totalling 350 grams of protein, 300 grams of carbohydrates and 40 grams of fat daily. However, I was getting headaches and always feeling hungry. Then I found out about glycemicindex.com. By choosing slow carbs, I was able to lose weight without feeling hungry and sustain my intense workouts. Five days a week I did 30 minutes of high intensity cardio workouts and weight training, with 45 minutes of cardio on the weekends. After losing a total of 59 pounds and dropping my waist size from 42 inches to 32 inches, I placed second in my class at the body building contest.

But the real reward was how I felt: I hadn’t felt this good since I was in high school, when I’d first started weight lifting and strength training as a way to overcome the weak knees that prevented me from playing sports. Today, I still manage my franchise business, but because I enjoy seeing people undergo the same kind of transformation I went through I also have my own personal trainer business. My motto is that no one is ever too old to adopt a healthy lifestyle; the body has an amazing ability to heal and renew itself.’
www.davidleenall.com



Send Us Your Success Story!

Books, DVDs, Websites: What’s New?

The Low GI Diet
Revised and updated Australian and New Zealand edition.
Prof Jennie Brand-Miller, Kaye Foster-Powell and Joanna McMillan Price.



‘Can I say how easy the Low GI Diet is to follow, and also The GI Diet Cookbook is excellent. I’ve got so much more energy and feel really well on it.’ – Pernille

The Low GI Diet is the science-based, 12-week Action Plan built around low GI smart carbs and smart moves to help you lose up to 10 per cent of your current body weight. Each week you will have a food goal, an exercise goal, an activity goal plus some food for thought. This revised edition has been updated with more recipes plus your low GI Diet pantry, It also includes:

• The best way to balance protein and carbohydrate
• The tools and tips you need to maintain weight loss for life
• Quick and easy recipes, meal plans and a menu survival guide for eating out
• Simple and practical ways to build more activity into your day
• The at-a-glance GI tables.

ANZ edition: The Low GI Diet, Hachette Livre Australia; Hachette Livre NZ
UK edition: The Low GI Diet, Hodder Mobius
US edition: The Low GI Diet Revolution, Marlowe & Company

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.

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Translating GI News and www.glycemicindex.com
If you would prefer to read GI News or a page from glycemicindex in a language other than English, there is a very easy way to translate them (or any site for that matter), using a service provided by Altavista called ‘Babel Fish’. Simply head over to www.babelfish.altavista.com and copy and paste a block of text into the first window (up to 150 words), or enter the website address to translate an entire page into the ‘Translate a Web Page’ box. Next, select which language you would like the English text translated to from the drop-down menu. Click the Translate button and Babel Fish will do all the work for you in just a few seconds.

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