1 September 2019

GI News - September 2019

GI News

GI News is published online every month by the University of Sydney, School of Life and Environmental Sciences and the Charles Perkins Centre, and delivered to the mailboxes of our 97,000 subscribers. Our goal is to help people choose the high-quality carbs that are digested at a rate that our bodies can comfortably accommodate and to share the latest scientific findings on food and diet with a particular focus on carbohydrates, dietary fibres, blood glucose and the glycemic index.

Professor Jennie Brand-Miller, AM, PhD, FAIFST, FNSA
Editor: Philippa Sandall
Scientific Editor/Managing Editor: Alan Barclay, PhD, APD, AN
Contact GI News: glycemic.index@gmail.com

Sydney University Glycemic Index Research Service
Manager: Fiona Atkinson, PhD, APD, AN
Contact: sugirs.manager@sydney.edu.au

Like us on Facebook
Follow us on Twitter



STEP 1: KEEP PORTIONS MODERATE. Why? Potatoes are carb rich. A typical medium potato (150g/5oz) has around 20g carbohydrate to help power your day. They are what we call good carbs – they put a lot of really good stuff on your dinner plate like dietary fibre and essential micronutrients including vitamins C, B (B6, riboflavin, thiamin and folate) and the minerals potassium, magnesium, and iron. The easiest way to keep an eye on portion size, is to eyeball the serving sizes by dividing the dinner plate into three sections. Protein foods (1) and wholegrains/starchy foods (2) should each take up just a quarter of the plate. Cooked green veggies or salad veggies (or both) should fill the remaining half (3).

Healthy plate
STEP 2: CHOOSE A LOWER CARB POTATO. There are some varieties of potato with fewer carbs. We sourced five packaged brands with about 20–25% less carbohydrate than regular spuds. Because growing conditions affect the carb content, the producers test their spuds regularly to ensure they meet the lower carbs claim on the packaging.

POTATO Table 1
Catherine Saxelby at Foodwatch did some experimenting with Carisma and Spud Lite and reports they are good all-rounders for family fare: they boil, mash and bake nicely. Check out her reports on her website (see Read More). If you want to taste test: the team at GiLicious have shared a recipe with us which you can find in The Good Carbs Kitchen.

STEP 3: CHOOSE A LOWER GI POTATO. Most potatoes have high GI values averaging around 77 (globally). This is because whatever the variety, potato starch consists of amylopectin and amylose in a fairly constant ratio of 3:1. When we checked the database at www.glycemicindex.com; flicked through The Shopper’s Guide to GI Values, and trawled back issues of GI News we found one potato with a low GI and several with moderate values which are better choices for managing blood glucose.

POTATO Table 2
While the variety makes a difference, there are other factors that affect GI. Small, new season potatoes tend to have a lower GI than fully grown spuds left in the ground longer. The recipe changes things, too. Cooking spuds in their skins and serving them with a vinegary dressing lowers the GI. Mashing them with white beans does too as will letting them get cold and making a potato salad, thanks to the resistant starch factor. However, it doesn’t seem to make that much difference to the GI whether you bake, boil or mash a particular variety of potato.

STEP 4: WATCH THE GLYCEMIC LOAD. How high your blood glucose level rises and how long it remains elevated when you eat a food or meal containing carbohydrate depends on both the GI of the carbohydrate and the total amount of carbohydrate in the food or meal. We use the term “glycemic load” or GL to describe this total amount. You calculate GL by multiplying the GI of a food by its available carbohydrate content (carbohydrate minus fibre in the USA) in the serving (in grams), divided by 100 (because GI is a percentage).

A regular medium-sized (150g/5oz) boiled potato with a high GI (average 77) provides approximately 20g of available carbohydrate. Its glycemic load is 15 (77 ÷ 100 × 20 = 15). Eat two potatoes and that jumps to 30.

You can reduce the load by reducing the portion size of the potato, or by choosing potatoes with less carbohydrate, or potatoes with a low or lower GI.

  • A medium GiLicious potato which has a moderate GI (61) contains 15 grams of available carbohydrate. Its glycemic load is 9 (61 × 15 ÷ 100 = 9). 
  • A medium Nadine potato, which has a low GI (49) contains 20 grams of available carbohydrate. Its glycemic load is 10 (49 × 20 ÷ 100 = 10).
SPUD WATCH? As there are literally hundreds of commercially grown varieties of potatoes around the world, it's very likely there are other lower carb and lower GI spuds out there. We'll keep you posted as we find them. If you come across any, please let us know.

Read More:


ConscienHealth’s Ted Kyle reports on a meta-analysis of ketogenic diets for obesity in JAMA Internal Medicine that suggests that currently enthusiasm is outpacing the evidence. Shivam Joshi, Robert Ostfeld, and Michelle McMacken tell us: “Although the ketogenic diet has garnered much attention for the dietary treatment of chronic diseases such as obesity and type 2 diabetes, the evidence supporting its use is currently limited and the diet’s potential risks are real. Physicians and patients should continue to judiciously appraise the benefits and risks of the ketogenic diet in accordance with the evidence, not the hype.”
In the short term, a ketogenic diet can be quite impressive for weight loss. People have less hunger, eat less, and lose more weight. However, the long-term results are not nearly so impressive. Meta-analysis of data from studies that lasted more than a year shows a difference of less than a kilo versus lower fat diets. This is a case where statistical significance is clinically insignificant.

Likewise, we’ve seen sensational results in short-term studies of ketogenic diets in type 2 diabetes. But if you look at longer-term studies, the results are bland. Once again, a meta-analysis shows no difference in glycemic control.

Joshi et al point out that long-term risks merit your consideration. People report fatigue with keto diets that may be more annoying than anything. But other issues, including nutritional deficiencies, are possible. However, the most significant issue, they say, may come from limiting whole grains, fruits, and legumes in a person’s diet over the long term. Whole grains offer benefits for reducing the risk of cardiovascular disease, cancer, and mortality. Fruits and legumes are also quite beneficial.

It might be a good thing that keto diets are tough to maintain for the long term. Banishing beneficial foods from your diet is not something to do lightly, based solely on short-term benefits.

Read more:


We dipped into our book, The Good Carbs Cookbook, to share 7 low carb good carbs to put on the dinner plate.

BEETROOT. Its vibrant colours come from its betalain pigments – betacyanin in red purple beetroots, betaxanthin in golden and orange beets. A medium raw beetroot (about 90g or 3oz) has about 165 kilojoules (40 calories), 2g protein, no fat, 7g carbs (7g sugars), 3g fibre, 45mg sodium, 240mg potassium, and a moderate GI (64) when cooked/canned; the GL is low (4).

CAPSICUM. Red, orange, yellow, green, purple: capsicum’s crisp, juicy flesh sets the taste bar high. It’s no wonder they have made themselves at home in kitchens around the world sliced or diced into salads, or stuffed, stir fried, and roasted. A medium raw capsicum (about 90g or 3oz) has about 80 kilojoules (19 calories), 1.5g protein, 0g fat, 3g carbs (3g sugars), 1g fibre, 2mg sodium, 135mg potassium and a low GI and GL (estimated).

CARROTS. While its colour is eye-catching, it’s the sweetness that makes it popular raw and cooked as a crunchy snack or side dish, and in salads, soups, stir-fries, bakes and roasts. A medium-sized raw carrot (about 130g or 4½oz) has about 170 kilojoules (41 calories), 1g protein, no fat, 6g carbs (6g sugars), 5g fibre, 49mg sodium, 348mg potassium, and a low GI (39); the GL is low (2).

CELERIAC. Knobbly celeriac or celery root may not be one of the best-looking vegetables around, but it pays to get under its skin. Look for the smoothest skinned ones to make peeling easier and have a bowl of acidulated water on hand to help prevent discoloration as the flesh darkens once cut. A cup of grated celeriac (about 155g or 5½oz) has about 250 kilojoules (60 calories), 2.5g protein, no fat, 4g carbs (4 g sugars), 8g fibre, 33mg sodium, 686mg potassium and a low GI and GL (estimated).

EGGPLANT (AUBERGINE). The rich meaty flesh of this gorgeous, glossy, deep-tasting veg transforms into a wonderfully silky texture when pan fried, oven roasted, stuffed, mashed or pureed. A small raw eggplant (about 320g or 11oz) has about 295 kilojoules (70 calories), 3.5g protein, 1g fat, 8g carbs (8g sugars), 8g fibre, 16mg sodium, 540mg potassium and a low GI and GL (estimated).

ONIONS. Just about indispensable, onions are used on a daily basis in sauces, soups, salads, stews, stir-fries and roasts. They are one of the earliest cultivated vegetables. 1 medium raw onion (about 90g or 3oz) has about 130 kilojoules (30 calories), 1.5g protein, 0g fat, 5.5g carbs (4g sugars and 1.5g starch), 1.5g fibre, 12mg sodium, 124mg potassium, and a low GI and GL (estimated).

PUMPKIN. Boil and steam for a quick side dish or soup, but roast when you want concentrated flavour and creamy sweetness. Toss some seeds on the compost and bingo, you’ll find yourself with a pumpkin patch. A cup of raw diced pumpkin (about 120g or 4oz) has about 200 kilojoules (48 calories), 2.5g protein, 0.5g fat, 8g carbs (5g sugars/3g starches), 1.5g fibre, 1mg sodium, 414mg potassium, and a moderate GI (66) when cooked; the GL is low (5).

Read more:


The glycemic index, or GI, is an inherent property of carbohydrate-containing foods and beverages. It is a relative ranking from 0–100, describing the rate and extent to which available carbohydrate (total carbohydrate minus dietary fibre) is digested, absorbed and metabolised into glucose and released into the blood.

Glycemic index testing follows an international standard. Volunteers who have fasted overnight are given 50g of glucose in water as a reference food, and researchers measure their blood samples at eight intervals over a two-hour period. The data enables the researchers to plot a curve, where area under the curve (AUC) is set at 100. On a separate day, the volunteers fast overnight again, and are then given the test food containing 50g of available carbohydrate. The AUC of the test food is expressed as a ratio of that of the glucose reference and is used to calculate the GI value which is a percentage.

GI test curve
Low GI foods (55 and under) are characterised by a slower and lower rise in blood glucose levels. High GI foods (70 and over) are characterised by a faster and higher rise and fall in blood glucose levels.

But speed of digestion is only one part of the story. Quantity counts. How high blood glucose actually rises and how long it remains high after we eat a meal containing carbohydrate foods depends on both the amount of carbohydrate in a food or drink as well as its glycemic index. Researchers from Harvard University and the University of Toronto came up with a term to describe this “speed/quantity” combo: glycemic load (GL). It is calculated by multiplying the GI of a food by the available carbohydrate content (carbohydrates minus fiber) in the serving (expressed in grams), divided by 100 (because GI is a percentage). (GL = GI/100 x available carbs per serving.)

For example, a typical medium-size apple has a glycemic index of 38 and contains 15 grams of available carbohydrate. Therefore, its glycemic load is 38÷ 100 × 15 = 6. If you are hungry, and the apples are particularly crispy, juicy, and delicious, and you eat two, the overall glycemic load of this snack is 12. If you have three, it’s 18.

One unit of glycemic load is equivalent to 1 gram of pure glucose. High GL foods and beverages have a GL value of 20 and above; medium GL foods and beverages have a GL value between 11 and 19; and low GL foods and beverages have a GL value of 10 and under.

What does this all mean for our health and wellbeing? The higher the glycemic load of a food or meal, the more insulin your pancreas needs to produce to drive the glucose into your cells. When we are young, our pancreas is able to produce enough insulin to cover the requirements of high-glycemic load foods and meals, but as we get older, it may no longer be able to cope with higher insulin requirements. This is when type 2 diabetes and other “lifestyle” diseases can start to develop.

In population studies, the GL simultaneously assesses the effect of available carbohydrate and GI on the risk of type 2 diabetes. GI and GL are calculated for the whole diet and adjusted for energy (kilojoules or calories) to help reduce confounding (e.g., the larger a person the more energy they require to maintain their body weight). Around the world, the average adult consumes around 2000 calories (8400 kilojoules) each day, so this is commonly used as the standard comparator.

The most recent systematic review and meta-analysis of population studies found that people consuming a diet with an average GI of 76 have an 87% higher risk of developing diabetes than people consuming a diet with an average dietary GI of 48. The simplest way to reduce average dietary GI is to replace high GI foods and beverages with lower GI alternatives within a particular food group.

Swap it
Similarly, the recent systematic review and meta-analysis found people consuming a diet with a GL of 257g per 2000 calories have an 89% higher risk of developing diabetes than people consuming a diet with a GL of 73g per 2000 calories.

Because GL is the product of GI and available carbohydrate, you can reduce it by either consuming a low GI diet (e.g., aim for an average GI less than 48), or by consuming less available carbohydrate (e.g., aim for between 130–230 grams per day if you consume 2000 calories (8400 kilojoules) per day), or both.

For example, for people who typically consume a relatively high carbohydrate diet (e.g., greater than 230g per day) with a high average GI (greater than 70), reduce average daily available carbohydrate intake to 165g and GI to 45 for an average daily GL of 74g per 2000 calories, keeping type 2 diabetes risk to a minimum. An example meal plan could look something like this:

Low GL meal plan

Read more:

Dr Alan Barclay
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.


Was it the rock-star chef Yotam Ottolenghi, or was it cauliflower rice that has created such an aura around this humble brassica vegetable? I’m going with Ottolenghi says dietitian Nicole Senior. Why? Because he’s all about deliciousness and flavour and a food culture that has lasted for ages and not a fad that has tarnished the name of all carbohydrates. And there are so many more delicious ways to enjoy cauliflower than smashing it to smithereens and imagining (very hard) that its potato.


Cauliflower is having its moment in the sun. It was never really in the shade as it has been trundling along for years in the form of cauliflower cheese (what’s not to love?), but since Ottolenghi made vegetables cool again and showed us how to cook them in delightful ways, cauli’s reputation has ramped up a notch or three. From a new take on cauliflower cheese with mustard, cumin and curry, a gorgeous salad with pomegranate and pistachios, a warming side dish with coconut cream and chilli, or cauliflower “steaks” with Middle Eastern Spices, Ottolenghi has indeed written the book on how to make this sculptural looking vegetable into something marvellous and irresistible.

There are many more beautiful recipes but my absolute go-to weeknight fast and simple approach is to cut a whole cauliflower into four quarters right down the stem, dress with crushed garlic and olive oil and roast until tender (I stick it in the BBQ but a hot oven will do just as well). It is simply divine and I can potter about doing the other bits of the meal while it takes very good care of itself. Equally, you could throw it into a roast vegetable medley and it will make beautiful mouth-music with other veggies who like the lick of fire such as potato, pumpkin (squash), eggplant (aubergine), capsicum (sweet pepper), carrot and parsnip.

What makes all this cooking talk even more appealing is learning just how good is it for your health. Cauliflower, like other vegetables in the brassica family (also called cruciferous vegetables because of their cross shaped flowers), contain phytochemicals called flavonoids and glucosinolates that help support your immune system and may even reduce cancer risk. It is also rich in vitamin C for healthy gums, folate for a healthy heart, vitamin K for controlling inflammation and fibre for good digestive health. And having high water content and rich flavour while also being low in kilojoules, it helps fill you up without filling you out.


And just when you thought we’d thought of everything to do with cauliflower, some smarty pants in the Australian horticultural industry thinks up the seemingly unthinkable – the cauliflower latte. From the “what-will-they-think-of-next” basket, comes an experimental milky coffee with 7g of cauliflower powder per cup that was served up to delegates at a horticultural industry conference. The baristas couldn’t keep up with demand! The word is it added a creamy texture and took the bitter edge off the coffee. The idea behind it is to use up otherwise wasted fresh cauliflower by transforming it into a dry powder. The powder could also be used in a range of other foods such as bread and improve vegetable intake as well as reduce food waste. I thoroughly approve both these concepts but I can’t help thinking if we all cooked cauli like Ottolenghi, we’d gobble up all the fresh cauliflower there is going and there’d be no waste whatsoever.

Nicole Senior  Nicole Senior is an Accredited Nutritionist, author, consultant, cook, food enthusiast and mother who strives to make sense of nutrition science and delights in making healthy food delicious.   Contact: You can follow her on Twitter, Facebook, Pinterest, Instagram or check out her website.


0:10 Prep • 0: 30 Cook • 6 Servings • Easy

1 medium cauliflower
2 tablespoons olive oil
sea salt flakes
¾ cup raw buckwheat groats, rinsed
⅔ cup medium pitted black olives, roughly chopped
2 tablespoons salted capers, rinsed and drained
3 tablespoons toasted pine nuts
2 tablespoons currants

1 garlic clove, crushed
1 handful parsley, chopped
⅓ cup olive oil
2 tablespoons lemon juice
sea salt flakes and freshly ground pepper

Preheat the oven to 190°C/375°F (fan 170°C/325°F). Line a baking tray with baking paper. • Rinse the cauliflower and cut through the thick core into quarters. Cut each quarter into thick slices and put into a bowl. If you prefer, cut them into large florets. Pour over the oil, sprinkle with a little salt and toss. Arrange the cauliflower on the tray and roast for 20–25 minutes, or until crispy and slightly charred. Set aside to cool. • While the cauliflower is roasting, bring a pot of water to the boil, tip in the buckwheat and simmer for 8–10 minutes, or until al dente. Drain, rinse and leave to cool to room temperature. • Whisk together the dressing ingredients, adding salt and pepper to taste, to make a chunky thick dressing. Watch the amount of salt you use, as both the capers and olives will provide a briny tang. • Put the cauliflower, buckwheat, olives, capers, pine nuts and currants in a bowl. Pour over the dressing and lightly tumble together. Serve at room temperature.

Per serve 1505kJ/ 360 calories; 6g protein; 27g fat (includes 3.5g saturated fat; saturated : unsaturated fat ratio 0.15); 21g available carbs (includes 5.5g sugars and 15.5g starches); 5.5g fibre; 255mg sodium; 505mg potassium; sodium : potassium ratio 0.5.

The Good Carbs Cookbook, Murdoch Books.

The Good Carbs Cookbook  

0:20 Prep • 0: 30 Cook • 6 Servings • Spice night

300g (10oz) potatoes, cut into 3 cm (1¼in) cubes
350g (12oz) cauliflower, cut into small florets
2 tablespoons curry leaves, plus extra to serve
olive oil spray
1 brown onion, sliced
2 long green chillies, sliced, plus extra to serve
30g (1oz) piece fresh ginger, finely grated
2 teaspoons yellow mustard seeds
1 teaspoon cumin seeds
½ teaspoon ground turmeric
coriander (cilantro) sprigs, to serve
150g (5½oz) reduced-fat plain yoghurt

½ cup chickpea flour (besan)
½ cup wholemeal (wholewheat) flour
¼ cup rice flour
1 small handful coriander (cilantro), finely chopped
olive oil spray

To make the masala: Put the potatoes in a saucepan of water and bring to the boil over high heat. Reduce the heat and cook for 8 minutes. Add the cauliflower and cook for a further 2–3 minutes or until the cauliflower is tender and the potatoes are soft when tested with a knife. Drain the vegetables and set aside. • Lightly spray the extra curry leaves with olive oil. Cook in a large non-stick frying pan over medium heat for 1–2 minutes or until crisp. Remove from the pan and set aside. • Spray the frying pan with olive oil and place over medium heat. Cook the onion, stirring, for 2–3 minutes or until softened. Add the chillies, curry leaves, ginger, mustard seeds, cumin seeds and turmeric. Cook, stirring, for 2–3 minutes or until aromatic. Add the potatoes, cauliflower and ¼ cup water. Stir for 1 minute or until the mixture is combined and the potatoes are slightly mashed. Cover and keep warm while you cook the dosa.

To make the dosa: Combine the flours with 1¼ cups water and whisk to make a runny batter. Stir in the coriander. Spray a large frying pan with olive oil and place over medium heat. Add one-quarter of the batter to the pan, tilting and swirling to make a thin round. Cook for 2 minutes, then turn over and cook for 1 minute or until golden. Transfer to a plate and repeat with the remaining batter to make four dosa in total.

To serve: Divide the potato mixture among the dosa, fold over and top with the yoghurt, coriander sprigs, chilli and fried curry leaves. Sprinkle with freshly ground black pepper and serve.

Per serving Energy 1225kJ/290 cals; protein 13g; fat 4g (includes 1g saturated fat; saturated : unsaturated fat ratio 0.33); carbohydrate 48g (includes 9g sugars and 39g starches); 8g fibre; 50mg sodium; 1070mg potassium; sodium : potassium ratio 0.05.

Dr Alan Barclay, Reversing Diabetes, Murdoch Books.

Reversing Diabetes  

0:10 Prep • 0:15 Cook • 6 Servings • Easy

Photo: @megannevans.photography

1kg (2lb 2oz) GiLicious™ potatoes,
¼ cup (60ml) extra virgin olive oil
Juice of 1 lemon
1 tablespoon white wine vinegar
½ medium red onion, cut into 2cm (¾in) pieces or finely diced if preferred
1 cup Italian parsley leaves, coarsely chopped
Sea salt and ground black pepper to taste

Place potatoes in a saucepan of salted boiling water and cook until just tender. Drain potatoes and place in a bowl. • Whisk together the olive oil, lemon juice and vinegar in a separate bowl. Add dressing to the warm potatoes, together with the finely sliced or diced red onion and chopped parsley, and toss well. • Season with salt and pepper to taste and serve warm or cold.

Per serving Energy 725kJ/174 cals; Protein 4.9g; Fat 9.8g (includes 1.5g saturated fat; saturated : unsaturated fat ratio 0.18); Carbohydrate 18.5g (3.5g sugars, 15g starch), Fibre 4g; Sodium 221mg; Potassium 971mg (sodium : potassium ratio 0.23)



University of Sydney

This website and all information, data, documents, pages and images it contains is copyright under the Copyright Act 1968 (Commonwealth of Australia) (as amended) and the copyright laws of all member countries of the Berne Union and the Universal Copyright Convention. Copyright in the website and in material prepared by GI News is owned by Glycemic Index Foundation. Copyright in quotations, images from published works and photo libraries, and materials contributed by third parties including our regular contributors Alan Barclay, Jennie Brand-Miller and Nicole Senior is owned by the respective authors or agencies, as credited.

GI News encourages the availability, dissemination and exchange of public information. You may include a link to GI News on your website. You may also copy, distribute, display, download and otherwise freely deal only with material owned by GI News, on the condition that you include the copyright notice “© GI News, University of Sydney” on all uses and prominently credit the source as being GI News and include a link back to ginews.blogspot.com.au. You must, however, obtain permission from GI News if you wish to do the following: 

  • charge others for access to the work 
  • include all or part of the work in advertising or a product for sale, or 
  • modify the work. 
To obtain such permission, please contact ginewsfeedback@gmail.com

This permission does not extend to material contributed and owned by other parties. We strongly recommend that you refer to the copyright statements at their respective websites and seek their permission before making use of any such material, whether images or text. Please contact GI News if you are in doubt as to the ownership of any material.

Nutritional analysis To analyse Australian foods, beverages, processed products and recipes, we use FoodWorks which contains the AusNut and Nuttab databases. If necessary, this is supplemented with data from www.calorieking.com.au or http://ndb.nal.usda.gov/ndb/search.

Disclaimer GI News endeavours to check the veracity of news stories cited in this free e-newsletter by referring to the primary source, but cannot be held responsible for inaccuracies in the articles so published. GI News provides links to other World Wide Web sites as a convenience to users, but cannot be held responsible for the content or availability of these sites. All recipes that are included within GI News have been analysed however they have not been tested for their glycemic index properties by an accredited laboratory according to the ISO standards.

© ®™ The University of Sydney, Australia