1 April 2008

Food for Thought

Choose tricklers not gushers
Because there have been inconsistent findings from observational studies, the controversy over the effects of GI and the risk of lifestyle diseases has had that ‘how long is a piece of string quality’ about it.

The first meta-analysis to evaluate the association between the GI of the diet, and the risk of developing common lifestyle-related diseases, was published in the American Journal of Clinical Nutrition in March and provides additional evidence that diets with a high GI or a high GL will increase your risk of type 2 diabetes and heart disease. It also shows there is evidence for links between high blood glucose and gallstones and even some types of cancer. ‘The key message,’ says lead author Alan Barclay, ‘is that the GI of your diet is a predictor of your disease risk. Grandma was right, you are what you eat.’


Low GI foods (the ones that trickle glucose into your bloodstream) have benefits for everybody. Not only can they keep you feeling full longer, they help you achieve and maintain a healthy weight and provide you and your brain with more consistent energy throughout the day. They can also have a major effect on the way the body functions and whether or not you develop health problems. Alan Barclay explains why: ‘If you have constantly high blood glucose levels from eating a high GI diet, you may literally “wear out” your pancreas over time and eventually this can lead to pre-diabetes and type 2 diabetes.’

‘There’s also evidence from the studies that have been done that high blood glucose levels are linked to certain types of cancer, as well. This is because constant spikes in blood glucose from eating high GI gushers cause the body to release more insulin, and also increase a related substance called insulin like growth factor one (IGF-1). Both these hormones increase cell growth and decrease cell death, and have been shown to increase the risk of developing some types of cancer.’

‘Other research shows that a high GI diet tends to reduce “good” HDL cholesterol levels and raise triglycerides levels; bad news for cardiovascular diseases. And people with low HDL cholesterol and high triglyceride levels are more prone to gallstones.’

‘What it comes down to is that there’s a simple, cost-effective way for everybody to reduce their risk of developing diabetes and heart disease and enhance their quality of life. We all need to eat a healthy, low GI diet. I guess that simply means when it comes to carb-rich foods, choose the tricklers and reduce the overall GI of your diet.’

10 tips for reducing the GI of your diet

  • Aim to eat at least two serves of fruit and five serves of vegetables every day, preferably of three or more different colours. Tidbit: Fill half your dinner plate with veggies.
  • If you are a big potato eater, either have one or two Nicola, Almera or tiny chat potatoes. Tidbit: Make ‘mash’ replacing half the potato with cannellini beans.
  • Choose a low GI bread. Look for the GI Symbol or choose a really grainy bread, true sourdough bread or a soy and linseed bread.
  • Replace high GI breakfast flakes (real glucose gushers) with low GI alternatives like natural muesli, traditional porridge oats or one of the lower GI processed breakfast cereals.
  • Look for lower GI rices such as basmati, Doongara Clever Rice or Moolgiri medium grain rice and choose less processed foods or low GI wholegrains such as traditional rolled or steel-cut oats, or quinoa for porridge or pearl barley, buckwheat, bulgur, whole kernel rye, or whole wheat kernels.
  • Eat legumes (beans, chickpeas and lentils) often – home cooked or canned.
  • Include at least one low GI carb with every meal. You’ll find them in four of the food groups: fruit and vegetables; bread and cereals; legumes; low fat dairy or soy alternatives.
  • Choose low GI snacks – fresh fruit, a dried fruit and nut mix, low fat milk or yoghurt.
  • Vinegar and lemon or lime juices slow stomach emptying and lower your blood glucose response to the carbohydrate with which they are eaten. Tidbit: Get the salad habit and toss it in a vinaigrette dressing.
  • Limit refined flour products – cookies, cakes, pastries, pies, crumpets, crackers, biscuits irrespective of their fat and sugar content.

Two extra tips to reduce blood glucose spikes

  • Incorporate a lean protein source with every meal – lean meat, skinless chicken, eggs, fish or seafood, or low fat dairy, legumes or tofu if you are vegetarian.
  • Remember portion caution with carb-rich foods such as pasta, noodles and low GI rices. It’s all too easy to over-eat them. While they may be low GI choices themselves, eating lots of them will have a marked effect on your blood glucose.


Anonymous said...

Please avoid the use of Australian trade marks ans food names that are uncommon elsewhere. The more 'international' the food descriptions the better for all your website visitors!


Anonymous said...

Is it true that the law in Australia requires GI labeling on packaged food?

Ohio USA

Khimji Motta said...

Please give a table of low GI eatables indicating time of each of six meals. For Diabete 2 patient
low GI recipe foods/vegetables/fruits.
This is required for vegetarian person.

GI Group said...

Bob first: No the law in Australia doesn't require GI labelling on packaged food, but a number of companies are voluntarily having their products tested and signing up for the GI Symbol program. It really makes buying bread easier just looking for the Symbol. The Symbol is in fact an international trade mark, but manufacturers in other countries have been slower off the mark to sign up.

Brian: We agree that the more international the better. And it would make our lives easier, too. But in fact that's not possible nor appropriate necessarily with packaged refined food products. Cornflakes made in the UK by manufacturer A may have a different GI from those made in the US and Australia by the same manufacturer because the source of the wheat is different. It is vital to be specific. As for rice, it is important to specify brands/varieties as some are very high GI (like jasmine) and others borderline low/moderate like basmati. If you want to understand more about it, check out a copy of Jennie Brand-Miller's New Glucose Revolution

GI Group said...

Khimji, we can't give individual dietary advice. For this detailed information, you need to see a dietitian who can assess your specific needs. Jennie Brand-Miller's Diabetes and Pre-diabetes Handbook (called The New Glucose Revolution for Diabetes in the US), may be a helpful starting point.

Anonymous said...

Is bread made with spelt flour low or high GI?

Anonymous said...

I am controlling my Type 2 Diabetes with diet so I am an avid reader of the "contents" box on food products. This leads me to a question - 'why is it that salt content doesn't appear to rate a mention in comments about diet and diabetes? I have found a number of breakfast cereals and breads proudly displaying a "Low GI" symbol but containing as much as 5x the recommended maximum amount of salt (which I believe to be 120mg per 100g). In addition, many of these "Low GI" products can also contain 10%++ saturated fats which seems to defeat the purpose of aiming for a healthy diet.I would be interested in any comments regarding the trio of Low GI + low saturated fats + low sodium in regard to diabetes. - Ross

GI Group said...

We have been asked about spelt and farro on a few occasions. Use the Google bar in the right-hand column to check the various comments. However, in summary, farro (emmer) and spelt are older varieties of wheat that were replaced by higher yielding varieties that are easier to hull. Neither farro nor spelt (grains or flour) have been GI tested. However, we do know the GI of some breads made with spelt and the results are similar to other breads – if there are lots of visible grainy bits, the GI is lower.

GI Group said...

Re salt: We have passed this question on to our GI Group dietitians for comment and will post a reply as soon as possible.

Anonymous said...

I agree with the poster about using Australian trade marks and food names. I am in the USA and can identify with generic names - would be more helpful. And I love this website - great information.

Southeastern USA

GI Group said...

Re salt, here's what our dietitians say:

"Both high blood pressure and high cholesterol levels are risk factors for heart and other blood vessel diseases that are common complications in people with diabetes. Unsurprisingly, many people with diabetes have high blood pressure, and limiting your salt (sodium chloride) intake and increasing your potassium intake (e.g., eating more fresh vegetables and fruits) may help improve it, along with appropriate medication. Similarly, many people with diabetes have high LDL (“bad”) cholesterol levels and low HDL (“good”) cholesterol levels, and eating less foods high in saturated and trans fat, and proportionately more that are sources of mono- and poly-unsaturated fats, along with optimal amounts of low GI carbohydrates, and sometimes medication, will help deal with this.

To make a low salt claim in Australia, a food must not contain more than 120 mg of sodium per 100 g. Unfortunately, very few processed foods are able to meet this classification for a variety of reasons, so this claim is pretty rare. It’s important to note that this is not a recommended maximum amount as such, but a guide to help people choose low salt foods. The upper recommended level of sodium for Australian adults is 2,300 mg per day. The amount people actually consume depends on both the amount of sodium per 100 g of food and the serve size – both factors are equally important.

While the criterion for making a low saturated fat claim on foods is currently under review, it is indirectly included in the existing Australia New Zealand Food Standards Code as a saturated and trans fatty acid content less than 28% of total fat. Importantly, the recommendation to consume less than 10% of saturated fats is for total diets – not specific foods.

There are many low GI claims on foods and they are currently not regulated in Australia or elsewhere (this may change in the near future). As such, there are no criteria to limit low GI claims to healthier foods and buyers should beware. However, the GI Symbol Program, and its Glycemic Index Tested logo, has been established in Australia to help people identify healthier lower GI choices. One of the nutrient criteria that enables a food to carry the official Glycemic Index Tested logo is for sodium, and the cut-offs for each food category have been set to ensure only foods or drinks with reduced amounts of sodium are allowed to be part of the program. This does not necessarily mean that they contain less than 120 mg of sodium per 100 g however, but it does mean that they are among the best choices within their particular food category. Again, one of the nutrient criteria that enables a food to carry the official Glycemic Index Tested logo is for saturated fat (generally less than 20% of total fat), and the cut-offs for each food category have been set to ensure only foods or drinks with reduced amounts of saturated fat are allowed to be part of the program. Therefore, to choose the healthiest low GI alternatives within a food group, simply look for the Glycemic Index Tested logo.”