GI Update

GI Q&A with Prof Jennie Brand-Miller

Can you explain to me how low GI diets work for weight loss?
The most important reason is likely to be the effect on day-long insulin levels – low GI foods result in lower levels of insulin over the course of the whole day. The hormone insulin is not only involved in regulating blood glucose levels, but also plays a key part in fat storage. High levels of insulin mean the body is forced to burn carbohydrate rather than fat. Thus, over the day, even if the total energy burnt is the same, the proportions of fat to carbohydrate are different. Oxidising carbohydrate won’t really help you lose weight, but burning fat will.

Dr Emma Stevenson’s research which we have reported on in GI News over the years has demonstrated over and over that, compared with healthy conventional meals, low GI meals were associated with greater fat oxidation during episodes of gentle exercise in overweight volunteers.

People who are overweight have been shown to have high glycogen (carbohydrate) stores that undergo major fluctuations during the day. This suggests that glycogen is a more important source of fuel for them. If glycogen is being depleted and replenished on a regular basis (before and after each meal, for example), it is displacing fat from the engine. Each meal restores glycogen (especially if the food has a high GI value) and the cycle repeats itself. Carbohydrate ‘balance’, as it’s called, is turning out to be one of the best predictors of future weight gain.

The benefits of a low GI diet for weight control go beyond appetite and fat burning. When you first begin a diet, your metabolic rate drops in response to the reduction in food intake, which makes weight loss slower and slower. Research shows your metabolic rate drops much less, however, on a low GI diet than a conventional diet. If your engine revs are higher, you’ll not only lose weight faster, you’ll also be much less likely to regain it.

New GI values with Fiona Atkinson
Blue Diamond Almond Breeze beverages
The new values this month were tested by our colleagues in Toronto at Glycemic Index Laboratories. These unsweetened, non dairy beverages are low calories (and carbs) in a typical serving, lactose and casein free, contain no transfats or cholesterol and are a good source of calcium and vitamin A. You can use enjoy them as a snack, on your breakfast cereal, in your cooking, for making smoothies or sauces or for adding to a cup of coffee.

Almond Breeze® Original: GI 25
Per 8 fl oz (240 ml cup) serving you’ll get 40 cals (168 kJ), 1 g protein, 3 g fat, 2 g total carbs (includes 1 g fibre)

Almond Breeze® Unsweetened Vanilla: GI 25
Per 8 fl oz (240 ml cup) serving you’ll get 40 cals (168 kJ), 1 g protein, 3 g fat, 2 g total carbs (includes 1 g fibre)

Almond Breeze® Refrigerated Unsweetened Vanilla: GI 22
Per 8 fl oz (240 ml cup) serving you’ll get 40 cals (168 kJ), 1 g protein, 3 g fat, 2 g total carbs (includes 1 g fibre)

Almond Breeze® Unsweetened Chocolate: GI 22
Per 8 fl oz (240 ml cup) serving you’ll get 45 cals (189 kJ), 2 g protein, 3.5 g fat, 3 g total carbs (includes 1 g fibre)

Raw almonds have a GI of 25. For more information, check out the Blue Diamond Growers website HERE.

GI testing by an accredited laboratory
North America
Dr Alexandra Jenkins
Glycemic Index Laboratories
36 Lombard Street, Suite 100
Toronto, Ontario M5C 2X3 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

See The New Glucose Revolution on YouTube