Which foods have low-GI? David Goding investigates.

You’ve no doubt seen the signs: low-GI is the new low-fat, with food manufacturers slapping the claim on everything from quick rice to fortified breads. Trouble is, the glycaemic index of a standalone food means little. It’s the overall composition of a meal that matters: white bread with a truckload of chicken breast has a lower glycaemic index than white vegemite toast.

Likewise, wholegrain sourdough loses its charm when you pile it with honey. Rolled oats may be changed depending on the type of milk and toppings. The other gotcha is labelling.

What is considered low-GI?

Under Food Standards Australia New Zealand’s (FSANZ) labelling criteria, any product with a glycaemic index of 55 or less on a 100-point scale can be labelled ‘low GI’. As such it’s futile to obsess over counting the GI of every food you buy; a better approach is the looser rule of including all macros in each meal or snack. But having a bit of a clue can help avoid blood sugar crashes. Stick this in your green bag.

The scale

LOW <55: Slowly raises blood sugar and keeps it stable

HIGH >70 Causes a rapid spike. Prepare for the subsequent crash