1 March 2013

GI News—March 2013

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  • Jamie’s low GI 15-minute Falafel wraps/grilled veg & salsa;  
  • Take that (glycemic) load off your diet and reduce your risk of type 2 diabetes;  
  • Fat facts and fat fiction - the state of the evidence; 
  • Was ancient man a vegetarian asks Dr Rob Dunn; 
  • The Longevity Project;  
  • The scoop on pearl couscous;  
  • Three low GI recipes to enjoy.
This month sees some interesting studies on the benefits of a vegetarian diet especially for reducing your risk of heart disease and (if pregnant) gestational diabetes. So we asked Prof Jennie Brand-Miller for her tips on going vegetarian the low GI way. There's also a fascinating research piece on Neanderthals and new evidence about their diet, cooking and use of medicinal plants.

Good cooking, good eating, good health and good reading.

Editor
: Philippa Sandall
Web management and design: Alan Barclay, PhD
Contact email (for questions or permission to reproduce stories from this newsletter): info@gisymbol.com for technical problems or faults please contact smb.ginewstech@sydney.edu.au

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Food for Thought

What’s irisin? Glenn Cardwell brings us up to speed on this interesting hormone.  

Glenn Cardwell
Glenn Cardwell

‘Don’t you like to be the first person in your group to use a new word? Sitting at the dining table commenting: “Excuse me, you have a little bit of food on your philtrum”. Well now, rather than saying something dull like you have been out for a walk or a game of squash you can say that you have been increasing your irisin output. About a year ago, clever folk at Harvard University had a study published in the journal Nature. OK, it was a study done in mice, but it has really excited the research community and now we are seeing studies in humans too. In essence, it seems that when we exercise not only do we burn fat and sugar (glucose) we also produce a very interesting hormone called irisin.

Brown vs white fat cells Irisin then travels around the body and modifies fat cells by increasing the number of brown fat cells and reducing the number of white fat cells. This is good because brown fat cells burn fat while white fat cells store fat. And the brown fat cells keep burning fat after you have finished exercise. Simply put, exercise burns fat and helps create fat burning brown fat cells, courtesy of irisin. Wait, there’s more. Irisin also helps to fight insulin resistance, one key factor behind high blood glucose levels and type 2 diabetes.

More research coming There will now be a flux of research on irisin. A paper published in December 2012 showed that obese people had high levels of irisin, suggesting that more is being produced to help combat high blood glucose levels common in obesity. Irisin is not the only protein being secreted by the muscles. Active muscles produce hundreds of proteins, some doubtless acting as hormones, so irisin may be only one of a family of secretory peptides that act to keep us lean and healthy. They are part of the explanation why fit people live longer than those who watch endless hours of mind-altering, light-emitting technology.

What does it all mean? Be active. Be fit. Don’t wait for irisin tablets or injections. We have been disappointed in the past with weight loss breakthroughs. Early research like this just helps us to marvel and understand the human body. Once a few more studies are done then expect, about March 2014 I’d say, the charlatans to spruik potions that ‘boost your irisin'. Just roll your eyes and go for a walk and boost your own for free, while getting some vitamin D and a mental refresher at the same time.’

 Glenn Cardwell is an Accredited Practising Dietitian. Make sure you check out Glenn's website.

What’s New?

Fat facts and fat fiction.  
Dietary advice about fat is always controversial, and even experts disagree about what recommendations are supported by current evidence. Kevin Lomangino, editor of Clinical Nutrition Insight contributed to the recent US Consumer Reports piece (which was also extensively edited and reviewed by nutrition scientists). In a Guest Post on Dr Yoni Freedhof’s blog, Weighty Matters, he provides more detail and links to the evidence that the authors of the Consumer Reports piece considered. ‘Although I don’t harbor any illusions about changing people’s strongly held beliefs about food, I do believe that our recommendations are sound and were based on the best scientific evidence available’ writes Kevin. Check out the state of the evidence on fats HERE

Does sugar cause diabetes? 
A new study in Plos One reports an association between global sugar availability and diabetes prevalence. Despite the headline hype, this study does not in fact provide any strong new evidence that sugar causes type 2 diabetes. Many other better designed studies already provide much stronger evidence that sugar does in fact not cause diabetes. The GI and GL are much more powerful predictors of type 2 diabetes risk.

What sort of study is this? It is an ecological study that examines the role of global sugar availability (using FAOStat data) in the diabetes (using IDF data) and obesity (using WHO data) epidemic. It covers a relatively short time frame of 10 years (2000– 2010) given it uses prevalence rates (not incidence rates – or new cases). Why does that matter? Well, ecological studies like this can show an association. Only randomised controlled trials can prove causality.

What did the study find? The analysis found a small (1.1% increase) but statistically significant association between sugar availability (kilojoules from sugar) and prevalence of diabetes. However, obesity was a much more powerful predictor of diabetes prevalence than sugar availability. Sugar availability was not associated with obesity prevalence. The authors attempted to control for differing definitions of obesity in people from different ethnic backgrounds by using a BMI greater than 25 (overweight in Western populations) as the cut off. But, overweight in many ethnic groups (e.g. Asian or Indian) is defined as a BMI greater than 23, as metabolic disturbance occurs at much lower BMI levels in these ethnic groups than in Western populations. To further confound the results, the researchers did not include other useful body composition measures like waist circumference in their model. When it comes to diabetes, where you carry excess weight really does matter as readers of GI News will know.

What is missing? The study does not discuss any data from the many cohort studies that have found either no association between sugar intake and diabetes risk or a negative association – increased sugar consumption associated with decreased risk of developing type 2 diabetes. If the aim of the paper was to have a balanced discussion of the role of sugar in the development of type 2 diabetes, then the authors should have included evidence from these types of studies in their discussion as it is more powerful than evidence from ecological studies.

What’s the bottom line? Good evidence from systematic reviews of randomized controlled trials show that the best way to reduce the risk of developing type 2 diabetes is to consume 2000-2500 less kilojoules (500-600 calories) each day by eating less fat, and in particular to reduce the intake of saturated fat and increase the intake of dietary fibre. Of course, some people may also reduce their energy intake by reducing the amount of added sugars that they consume.

Vegetarianism can reduce risk of heart disease by a third. 
The risk of hospitalisation or death from heart disease is 32% lower in vegetarians than people who eat meat and fish, according to a new study in the American Journal of Clinical Nutrition. ‘Most of the difference in risk is probably caused by effects on cholesterol and blood pressure, and shows the important role of diet in the prevention of heart disease,’ says lead author Dr Francesca Crowe.

The analysis looked at almost 45,000 volunteers from England and Scotland enrolled in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Oxford study, of whom 34% were vegetarian. The volunteers were tracked until 2009, during which time researchers identified 1235 cases of heart disease. They found that vegetarians had lower blood pressure and cholesterol levels than non-vegetarians, which is thought to be the main reason behind their reduced risk of heart disease. Vegetarians typically also had a lower BMI and fewer cases of diabetes, although these were not found to significantly affect the results. Adjusting the results to exclude the effects of BMI, vegetarians remained 28% less likely to develop heart disease. – Eurekalert
 
A meaty risk factor for gestational diabetes? 

‘Whether you are pregnant or trying to conceive, good nutrition is an essential part of optimising your own health and that of your unborn baby. Eating well prior to conceiving ensures your body is in the best position to support a pregnancy, while good nutrition during pregnancy is essential to provide the nutrients your baby needs to grow and develop and those you need to stay healthy during your pregnancy,’ writes Prof Jennie Brand-Miller in The Bump to Baby Diet. A new study just published in Diabetes Care  reports that having higher intakes of animal protein, particularly red meat, was significantly associated with a greater risk of gestational diabetes. By contrast, substituting some healthy protein sources such as poultry, fish, legumes and especially nuts was associated with a lower risk. Commenting on this study, Prof Brand-Miller reminds us that: ‘observational studies like this don't prove cause and effect. It’s possible that this finding is confounded to some degree by the fact that women who eat a lot of red meat ALSO live a lifestyle that increases their risk of gestational diabetes – for example they may be women who don't like fruit and veggies, love salty food and rarely if ever exercise.’

Neanderthal medics? Evidence for food, cooking and medicinal plants.  
New research confirms ‘the varied and selective use of plants by Neanderthals’ says Professor Les Copeland from the University of Sydney. Until recently Neanderthals, who disappeared between 30,000 and 24,000 years ago, were thought to be predominantly meat-eaters. However, evidence of dietary breadth is growing as more sophisticated analyses are undertaken. Researchers from Spain, the UK and Australia combined pyrolysis gas-chromatography-mass spectrometry with morphological analysis of plant microfossils to identify material trapped in dental calculus (calcified dental plaque) from five Neanderthals from the north Spanish site of El Sidrón. Their results provide another twist to the story – the first molecular evidence for medicinal plants being used by a Neanderthal individual.

In the ten samples of dental calculus from five Neanderthals selected for this study, the researchers found chemical evidence consistent with wood-fire smoke, a range of cooked starchy foods, two plants known today for their medicinal qualities, and bitumen or oil shale trapped in the dental calculus. Evidence for cooked carbohydrates is confirmed by both the cracked/roasted starch granules observed microscopically and the molecular evidence for cooking and exposure to wood smoke or smoked food in the form of a range of chemical markers including methyl esters, phenols, and polynuclear aromatic hydrocarbons found in dental calculus.

The researchers say the starch granules and carbohydrate markers in the samples, plus evidence for plant compounds such as azulenes and coumarins, as well as possible evidence for nuts, grasses and even green vegetables, argue for a broader use of ingested plants than is often suggested by stable isotope analysis. According to lead author Karen Hardy: ‘The varied use of plants we identified suggests that the Neanderthal occupants of El Sidrón had a sophisticated knowledge of their natural surroundings which included the ability to select and use certain plants for their nutritional value and for self-medication. While meat was clearly important, our research points to an even more complex diet than has previously been supposed.’

Researchers in cave

Earlier research had shown that the Neanderthals in El Sidrón had the bitter taste perception gene. Now trapped within dental calculus researchers found molecular evidence that one individual had eaten bitter tasting plants. ‘The evidence indicating this individual was eating bitter-tasting plants such as yarrow and camomile with little nutritional value is surprising. We know that Neanderthals would find these plants bitter, so it is likely these plants must have been selected for reasons other than taste’ says co-author Dr Stephen Buckley.

The Longevity Project.  
This book is a fascinating addition to the burgeoning longevity bookshelf. The authors draw on an eight-decade-long Stanford University study tracing the lives of 1500 people (the Terman study) to find who lives a long, healthy life and why. If there’s a secret to old age, they report, it’s living conscientiously and bringing forethought, planning, and perseverance to your professional and personal life. Here’s an extract from the introduction to whet your appetite.

The Longevity Project book

‘Most books about health and longevity are cookbooks – literally or figuratively. When they aren’t giving you recipes (start Week 1 with spinach sautéed in garlic and olive oil) and food lists (an apple a day), they’re offering a list of dos and don’ts (do exercise for 30 minutes four times a week; don’t let your weight rise above a certain ratio to your height).

Exercise, diet, stress, and weight are indeed relevant to health, but in ways that vary from person to person. Lists of dos and don’ts are nearly impossible for most of us to follow for days, months, and years. Thankfully, the Terman study participants showed us that struggling with lists of specific health rules is unnecessary. The Terman men and women were born decades before running shoes, designer spas, and fancy medical tests were invented, yet many lived long, healthy lives. The point of describing our findings is not to lay out the factors that are likely to leave you the last one standing. Most of us, after all, would not wish to live extra years if they were years of constant decline and pain. But the fact is, those who live longer are also generally healthier throughout their lives. Most people who live to old age do so not because they have beaten cancer, heart disease, diabetes, or lung disease; rather, the long-lived have mostly avoided serious ailments altogether.

Because Dr. Terman began studying his participants when they were very young, many of the insights that emerged are helpful not only to adults looking to get on a healthier life path but also to those hoping to set their children on a good track. Many of our findings can help people rethink the potential long-term effects of their parenting decisions, as well as promote their whole family’s future health, happiness, and well-being.’ – The Longevity Project is available online and from good bookshops.

Get the Scoop

The scoop on pearl couscous. 
Unlike traditional couscous, pearl couscous which takes its name from its pearl-like shape and size is often described as a ‘toasted pasta specialty’. Like regular pasta, it is made from hard (durum) wheat and water. But instead of being dried, it is toasted in an oven. It has a rich, nutty flavour and a chewy texture, with a smooth, almost buttery, mouth feel. It makes a perfect side dish to meat, poultry, or fish instead of potatoes, rice, or traditional pastas or couscous. It cooks in around 10 minutes by the absorption method – just like rice – and you can also use it in a variety of dishes – just like rice and other pastas.

Where does it come from? Pearl couscous or ‘ptitim’ made their first appearance as a substitute for rice during the early days of Israel when there was not enough rice for everyone. Prime minister David Ben-Gurion turned to Ivgen Propper (one of the seven founders of the Osem company and the father of Dan Propper, who eventually became the company's CEO), asking him to come up with a wheat-based substitute for rice – and quickly. The company accepted the challenge and developed ‘baked ptitim’, made of hard wheat flour and roasted in an oven, a process that affords them a characteristic flavor and aroma. The success was instant and soon ptitim in the shape of small, dense balls (which the company dubbed ‘couscous’) were added to the original rice-shaped ptitim (known as ‘Ben-Gurion rice’).

Vegetarian dishes

Availability Today you can buy Osem Israeli couscous or Osem toasted pasta in supermarkets and health food stores around the world – or from Amazon! Here in Australia, it is marketed as Blu Gourmet Pearl Couscous (GI52) and is on the shelves in most supermarkets and many independent grocers and delis. It also has the GI Symbol. For those of you who need to count your carbs, ½ cup cooked pearl couscous has around 20g carbs and a GL of 10.

In the GI News Kitchen

American dietitian and author of Good Carbs, Bad Carbs, Johanna Burani, shares favourite recipes with a low or moderate GI from her Italian kitchen. For more information, check out Johanna's website. The photographs are by Sergio Burani. His food, travel and wine photography website is photosbysergio.com.

[JOHANNA]

Winter vegetable mix. 
Leave it to the Italians to take the humdrum vegetables that everybody has been eating all winter long and ZAP! them with shout-in-your-mouth flavor. What a combination of well groomed flavors! Feel free to adjust the dressing seasonings to appease your personal palate. And, if you find a little excess dressing pooling in your plate, do what the Italians do soak up every last drop with a piece of fresh crusty Italian bread! I like to use organic vegetables for this and of course Australian readers should opt for low GI Carisma potatoes. Servings: 10 x 1-cup portions

1 lb/450g new potatoes (about 20 small)
1 lb/450g cauliflower (about 5 large florets)
1 lb/450g broccoli (about 4 x 6-inch/15cm stalks)
12 kalamata olives, halved
½ tsp chopped capers
1–2 cloves garlic, minced
1/8 tsp anchovy paste
juice 1 lemon, freshly squeezed (about ¼ cup)
1 tsp sea salt (optional)
½ cup extra virgin olive oil

Winter vegetable mix

Place
a steamer basket in a large pot with 1–2 inches (3–5cm) of water. Cover and bring to a boil. Scrub unpeeled potatoes, cut in half widthwise and steam for 12 minutes. When cooked, spoon potatoes into a large, warmed serving bowl. Cover and set aside. In the meantime, wash cauliflower and broccoli, cut into 1-inch (2.5cm) pieces and set aside.
Bring water back to a boil. Add cauliflower to steamer basket. Cover and cook for 7 minutes, Then add to the serving bowl. Keep covered.
Bring water back to boil. Add broccoli to steamer basket. Cover and cook for 5 minutes then add to the serving bowl. Mix well. Gently add in olives.
Whisk together the remaining ingredients. Pour over the vegetables and mix thoroughly. Serve immediately.

Per serve 
800kJ/190 calories; 4g protein; 13g fat (includes 1.5g saturated fat); 17g available carbs; 3g fibre

Here's how you can cut back on the food bills and enjoy fresh-tasting, easily prepared, seasonal, satisfying and delicious low or moderate GI meals that don’t compromise on quality and flavour one little bit with our Money Saving Meals including this easy salad from Blu Gourmet Pearl Couscous.

Pearl couscous salad with vegetables and cashew nuts and a sesame dressing. 
This recipe from Blu Gourmet Pearl Couscous was created by Gabriel Gaté and is a great way to use up leftover vegetables. You’ll find more recipes on their website. Serves 6.

250g (9oz) pearl couscous
juice of 1 lemon,
2 tbsp salt-reduced soy sauce,
½ teaspoon sesame oil,
½ a red chilli, finely sliced,
3 tbsp extra virgin olive oil,
about 80g (3oz) roasted unsalted cashew nuts,
½ cup coriander leaves,
1 cup cooked corn kernels
200g (7oz) cooked green beans, cut into small pieces,
300g (10oz) cooked butternut pumpkin cubes

Pearl couscous salad with vegetables and cashew nuts  

Bring a large volume of salted water to the boil. Stir in the couscous and cook uncovered for 10 minutes. Drain the couscous, place in cold water to cool, then drain again.
Mix together the lemon juice, soy sauce, sesame oil, red chilli, olive oil, cashew nuts and coriander leaves in a serving bowl. Add the cold drained couscous and toss gently. Add the vegetables and toss together very gently before serving.

Per serving 
Energy: 1640kJ/ 390 cals; protein 11g; fat 17g (includes 2.5g saturated fat and 0mg cholesterol); available carbs 46g; fibre 4g

Jamie’s 15 Minute Meals. 
The cover describes the recipes in this book as ‘delicious,’ ‘nutritious’ and ‘super-fast’. And they are. We particularly like the fact that many are also low. Check out www.jamieoliver.com for more information.

Falafel wraps/grilled veg & salsa.
Recipe © Jamie Oliver 2012. Serves 4.

Falafel
1 x 400g (14oz) tin of mixed beans
1 x 400g (14oz) tin of chickpeas
1 lemon
1 tbsp harissa
1 heaped tsp allspice
1 heaped tbsp plain flour
1 bunch of fresh coriander
olive oil
Sides
2 mixed-colour peppers
4 spring onions
8 small wholewheat tortillas
1 tbsp Lingham’s chilli sauce
250g (8oz) low-fat cottage cheese
optional: pickled red cabbage
 Salsa
1 big handful of mixed-colour ripe tomatoes
½–1 fresh red chilli
½ a clove of garlic
1 lime

Ingredients out • Food processor (bowl blade) • Large frying pan, medium heat • Griddle pan, high heat

Falafel wraps/grilled veg & salsa
Photography © David Loftus, 2012

Drain the beans and chickpeas and put them into the processor • Finely grate in the lemon zest, then add a pinch of salt and pepper, the harissa, allspice, flour and coriander stalks (reserving the leaves) • Blitz until smooth, scraping down the sides of the processor if needed • Scrape out the mixture and use clean, wet hands to quickly divide and shape it into 8 patties about 1.5cm (¾in) thick • Put 1 tablespoon of oil into the frying pan and add the falafels, turning when golden and crisp.
Rip the seeds and stalks out of the peppers, tear each one into bite-sized chunks and put on the griddle pan with the trimmed and halved spring onions and a pinch of salt and pepper, turning when charred • Put the tomatoes, chilli and half the coriander leaves into the processor • Squash in the unpeeled garlic through a garlic crusher, squeeze in the lime juice, whiz until fine, then season to taste and pour into a serving dish.
Pop the tortillas into the microwave (800W) for 45 seconds while you marble the chilli sauce into the cottage cheese • Squeeze the juice of half the zested lemon over the charred veggies, then take with the falafels to the table, scattering everything with the rest of the coriander • Let everyone assemble their own wraps, and serve with pickled red cabbage, if you like.

Per serve 
1740kJ/415 calories; 28g protein; 7g fat (includes 1.4g saturated fat); 50g available carbs; 15g fibre

Jamie’s 15 Minute Meals

Jamie’s 15 Minute Meals is published by Michael Joseph, Penguin and is available in good bookshops and online.

We Are What We Ate

Was ancient man a vegetarian? Robb Dunn reviews the evidence. 
First published in Scientific American. This edited and updated extract reprinted with their kind permission.

Rob Dunn
Rob Dunn

‘Right now, one half of all Americans are on a diet. The other half just gave up on their diets and are on a binge. Collectively, we are overweight, sick and struggling. Our modern choices about what and how much to eat have gone terribly wrong. The time has come to return to a more sensible way of eating and living, but which way? An entire class of self-help books recommends a return to the diets of our ancestors. Paleolithic diets, caveman diets, primal diets and the like, urge us to eat like the ancients. The idea that we might take our ancestral diet into consideration when evaluating the foods on which our organs, cells and existence thrive, makes sense. But there are big questions to be answered before we do. The first is which paleo diet we should consider? The one from twelve thousand years ago? A hundred thousand years ago? Forty million years ago?

What is your ancestral diet, the one our ancestors ate when most of the features of our guts were evolving? If you want to eat what our ancestors spent the most time eating during the largest periods of the evolution of our guts, you should eat fruits, nuts, and vegetables – especially fungus-covered tropical leaves. A new paper suggests even Neanderthals – our north country cousins and mates – may have eaten much more plant material than previously suspected. (See Neanderthal Medics in News Briefs in this issue.)

But didn’t the guts of our ancestors evolve as their diets later changed? Yes, some. But these changes, at least the ones we know about so far, seem to have had as much to do with the shift to processed and agricultural foods as they did with the shift to meat per se. Some of the changes that occurred along with the shift to processed (burned, mashed) foods and later agriculture happened to everyone. Our guts shortened, for example. But others were stories not of humans but of individual human or hominid lineages. With agriculture, some human populations evolved extra copies of amylase genes, arguably so as to better be able to deal with starchy foods. The case of agriculture is the most clear. With agriculture, several human populations independently evolved gene variants that coded for the persistence of lactase (which breaks down lactose) so as to be able to deal with milk, not just as babies but also as adults. Drinking milk of another species as an adult is weird, but some human populations have evolved the ability. With agriculture, the species in our guts seem to have evolved too. Some populations of humans in Japan have a kind of bacteria in their guts which appears to have stolen genes for breaking down seaweed, a foodstuff that became popular along with the post-agricultural Japanese diet. With agriculture, human bodies changed so as to cope with new foods. Our bodies bear the marks of many histories. As a result, if you want to eat what your body ‘evolved to eat’ you need to eat something different depending on who your recent ancestors were.

We already TAKE our individual histories into account in our diets to some extent. If your ancestors were dairy farmers, you can drink milk as an adult without trouble, you’ve ‘got lactase.’ But if they were not, you tend to get diarrhea when you drink milk and so you probably avoid the stuff (lest your friends avoid you). Yet, the truth is, for most of the last twenty million years of the evolution of our bodies, through most of the big changes, we were eating fruit, nuts, leaves and the occasional bit of insect, frog, bird or mouse. And so while some of us might do well with milk, some might do better than others with starch and some might do better or worse with alcohol, we all have the basic machinery to get fruity or nutty without trouble.

Interestingly, if our gut bacteria responded rapidly to shifts in diets toward more meat during the stone age, they might be expected to have shifted again when we began to farm, at least for those of us with ancestors who began to farm early. When our gut bacteria met up with our agricultural diets, beginning twelve thousand years ago or so, they would have begun to compete with new microbial species that kicked ass at living off wheat, barley, corn, rice or any of the other grasses that have come to dominate the world, sometimes at our expense. This may even mean that which diet is best for you depends not only on who your ancestors were, but also who the ancestors of your bacteria were.

In this light, the second question is what should we eat? One might hope that the answer would be that we could simply point to an ancestor in one place or time and eat what they ate. Our historic diets should inform what we eat today. But they are not an answer, not on their own, for what we should eat today. The past was not idyllic. It was difficult. Our ancestors died younger than we do. They suffered many fates we would not wish upon ourselves or upon our children. If our ancestors looked into the future and saw us they would ask, “How do we get what they have?” In a way, our problems actually stem from our ancestors. We have become better and better at producing more and more of those foods that our ancestors would have craved (but could not get in excess). Our ancestors had taste buds that called out for sweets, but they only found the rare and dangerous honey of bees. Our ancestors had taste buds that called out for salt, but they had to search out salt licks or the salty blood of animals. Our ancestors had bodies that cried out for the quick energy of easy to digest foods but they had, for most of our history, the harder to digest food of raw fruits, nuts and vegetables. The great success and difficulty of humanity in terms of our diets is that we have been able to produce each thing our bodies crave in excess; we have met our ancient paleo cravings in spades. The trick is to figure out what would make our bodies most healthy, based on the insights of modern nutrition and ancient context of our ancestral diets (plural). It is no great insight that many of us would be healthier if we ate more fruit and nuts like our earlier ancestors, but this is not because they had everything so right. It is because in trying to make everything our ancient bodies crave we have gotten it so wrong.  

Rob Dunn is a biologist and writer in the Department of Biology at North Carolina State University. His writing has appeared in Natural History, BBC Wildlife Magazine, Scientific American, Smithsonian Magazine, National Geographic and other magazines. You can read his articles on his website:

The Wild Life of Our Bodies

Rob’s latest book, The Wild Life of Our Bodies, examines the long human relationship with other species (be they tapeworms or tigers) and how changes in those relationships are affecting our health and well being. You can buy it HERE.

GI Symbol News with Dr Alan Barclay

Alan Barclay
Dr Alan Barclay

Reduce that load and reduce your risk. 
A-grade research (think Olympic gold level) from around the world over the past 20-plus years has shown pretty conclusively that type 2 diabetes is not caused by any single nutrient or food (such as sugar) but from a combination of diet and lifestyle risk factors.

The reason why there is no relationship between sugars and diabetes risk is simple: sugars only comprise about half of the carbs we eat, the other half comes from starches and both sugars and starches have a major impact on our blood glucose and insulin levels. So you can see that it makes no sense to focus on only one type of carbohydrate and ignore the other – especially as the GI values of both vary substantially. On the other hand, a systematic review we carried out in 2008 found those eating the highest GI diet had a 40% higher risk of type 2 diabetes than those with the lowest GI diet. Indeed, when it comes to pointing the finger at diet and diabetes risk, the strongest evidence to date is that it’s the overall glycemic load of your diet (i.e. the total amount of carbohydrate x GI) that’s the biggest potential problem.

The latest systematic review published on the topic provides a powerful addition to the evidence base. Researchers combined the results of 24 prospective cohort studies from around the globe, including 125,000 people, and found that high GL diets increased the risk of developing type 2 diabetes by 45%. Like our 2008 systematic review the authors found that the validity of the tools used to assess peoples food and drink intakes had a significant effect on the strength of the association. If only the studies with the highest validity are included in prediction models, the association between GL and risk of type 2 diabetes increases to an enormous 105%.

This latest review also provides some very practical targets to help people reduce their risk of developing type 2 diabetes. They found that you need to ensure the average GL of your daily diet is less than 95 if you consume 8400kJ (2000 Calories) per day (the average intake for adults in developed countries). This can be achieved through a number of ways. For example, either consume:

  • 200g carbohydrates a day with a GI of 50, or 
  • 225g carbohydrates a day with a GI of 45, or 
  • 250g carbohydrates a day with a GI of 40 
FYI, 200g carbs would be roughly equivalent to eating a bowl of breakfast cereal with milk and a piece of fruit for breakfast (total ~45 g of carbohydrate), 2 slices of bread, a piece of fruit and a small tub of yoghurt for lunch (~60 g), a cup of cooked rice/pasta/noodles/etc... for dinner (~45 g), and fruit for dessert (~15 g) and 1 piece/glass/tub of fruit/milk/yoghurt (~15 g each) for inbetween meal snacks and/or supper.

We have found in our research that you actually don’t need to worry too much about counting carbs or GI. In fact you can achieve these targets by choosing moderate portions of low GI carbohydrates for most of your meals and snacks each day. Check out our simple tips for lowering the overall GI of your diet HERE.  

The GI Symbol, making healthy low GI choices easy choices

New GI Symbol

For more information about the GI Symbol Program
Dr Alan W Barclay, PhD
Chief Scientific Officer
Glycemic Index Foundation (Ltd)
Phone: +61 (0)2 9785 1037
Mob: +61 (0)416 111 046
Fax: +61 (0)2 9785 1037
Email: alan.barclay@gisymbol.com
Website: www.gisymbol.com

GI Update with Prof Jennie Brand-Miller

Prof Jennie Brand-Miller answers your questions. 

Jennie


I have never been much of a meat eater and have decided to go completely vegetarian. Can you give me some tips on making sure that I get all the nutrients I need. 
Building your diet around plant foods such as wholegrains, legumes, fruits and vegetables, nuts and seeds gives you all the nutrients you need for long-term health and wellbeing.

Getting plenty of protein It’s not necessary to eat meat, chicken or fish to get enough protein. Plant proteins can provide you with all the essential amino acids you need. Stock your pantry with legumes, wholegrains (such as grainy breads, muesli, quinoa, amaranth, brown rice, pearl barley and rolled oats), nuts (particularly almonds, Brazil nuts, cashews and peanuts), and seeds (sesame seeds, tahini paste, and pumpkin seeds). They are also good sources of iron and zinc typically sourced from protein-rich foods. It’s even easier if you eat dairy foods and eggs.

Know your fats For vegetarians and non-vegetarians alike, the message today is know your fats. Focus on the good fats and give the bad ones the flick. Since vegetarians tend to consume more omega 6 and less omega 3, focus on including foods which are specifically sources of omega 3 such as linseeds, chia seeds and flaxseed oil along with walnuts, pecans and soya beans. When preparing meals, try using a variety of different oils, depending on the dish – a mono-unsaturated oil such as canola or olive oil is a good idea for cooking as they are both ‘omega-neutral’ meaning they will not worsen the balance of omega 6: omega 3.

Choosing quality carbs To make sure you are eating quality carbs, opt for whole or minimally processed foods that also provide fibre, protein, vitamins and minerals. Eat a wide variety of these foods including:

  •  Cereal grains such as barley, buckwheat, bulgur, maize, millet, oats, quinoa, rice, rye, spelt and wheat and the enormous variety of foods made from them including bread, breakfast cereals (with minimum if any added sugar), rice, pasta, noodles and couscous. Look for wholegrain varieties. 
  • Legumes like lentils, beans, chickpeas and split peas – home cooked or canned. Add them to meals and snacks and you will reduce the overall GI of your diet. 
  • Starchy vegetables like potatoes (Carisma is low GI), taro, yam and sweet potato plus parsnip, beetroot, pumpkin, carrot, turnips and peas and sweetcorn. 
  • Fruit – fresh, canned (in natural juice) or frozen. It doesn’t provide nearly as much carbohydrate as the cereal grains. Dried fruits are an exception, with many being as high in carbohydrate as cereals. 
  • Dairy foods like low fat milk and yoghurt or calcium-enriched soy. Cheese is not a source of carbohydrate as the lactose (milk sugar) is removed in processing. 
Check out the database at www.glycemicindex.com or the 2013 Shopper’s Guide to GI Values to find the lower GI products.

Low GI vegetarian cookbook

This is an extract from The Low GI Vegetarian Cookbook. It is available from Amazon and good bookshops.  

GI testing by an accredited laboratory
North America

Dr Alexandra Jenkins
Glycemic Index Laboratories
20 Victoria Street, Suite 300
Toronto, Ontario M5C 298 Canada
Phone +1 416 861 0506
Email info@gilabs.com
Web www.gilabs.com

Australia
Fiona Atkinson
Research Manager, Sydney University Glycemic Index Research Service (SUGiRS)
Human Nutrition Unit, School of Molecular and Microbial Biosciences
Sydney University
NSW 2006 Australia
Phone + 61 2 9351 6018
Fax: + 61 2 9351 6022
Email sugirs@mmb.usyd.edu.au
Web www.glycemicindex.com

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