1 November 2007

Feedback—Your FAQs Answered

Why is the GI of Frosties (55) lower than Kellogg’s Corn Flakes (77), Crunchy Nut Corn Flakes (72) and Skippy Cornflakes (93)?
Many people assume that the higher the sugar content, the higher the GI. But in fact, starch in cornflakes is very rapidly digested and absorbed (it's been fully 'gelatinised' during processing), giving the product its high GI. When you incorporate sugar into the recipe, you reduce the GI for two reasons:

  • Sucrose has a lower GI than the starch in cornflakes.
  • The presence of sugar reduces the ability of the starch to gelatinise by tying up water molecules.
Both effects work together to give Frosties its lower GI. And by the way, there is absolutely no difference in calories or nutrient content of Frosties vs cornflakes. Processed starch is pretty empty of micronutrients, just like sugar.


So what you are saying is that even though Frosties has a much lower GI than cornflakes, there would be no benefits in eating the one with the lower GI? I thought that the lower GI was what I was supposed to look for when choosing breakfast cereals
When choosing foods the GI isn't meant to be used on its own. The nutritional benefits of foods are many and varied and that's why we suggest you base your food choices on the overall nutritional content along with the amount of saturated fat, fibre, salt and of course the GI value. So although Frosties have a lower GI, nutritionally they are much the same as cornflakes. However, they won’t spike your blood glucose in quite the same way as cornflakes will, so would be a better choice for sustained energy. But better still, opt for a nutrient-rich, low GI breakfast cereal such as wholegrain oats, muesli or a high-fibre breakfast biscuit.


Anonymous said...

I was going back through some of the past newsletters and found that you had discovered a lower GI (58) potato called Nicola. You mentioned that they are available in major supermarkets, but I have not been able to locate this potato in Woolworths or our other fresh fruit and vegetable store in our local shopping centre (Sydney, NSW, Australia). Does it have another name that it goes by or is it the white washed potatoes that do not have a name listed? Can you please post some more information about locating this particular potato. Also, do you know if the GI of this potato varies very much when boiled, baked, or mashed - Or which way was the healthiest to cook it? Thanks

Anonymous said...

Nicola potatoes, like many types of potato, seem to be seasonal. They are apparently grown on both the Atherton Tableland and in Tasmania. And yes they are hard to find. But Woolworths do stock them in season as do Harris Farm. We'll follow up with our spud experts about when you can expect to see them in store again. No they aren't the white, washed, no-name ones. The GI testing was with boiled potatoes and that (or steaming) would be best. Mashing will increase the GI of potatoes. But if you love mash, why not mash them with some white beans such as cannellini to lower the overall GI. And baking would be fine, but watch the amount (and type) of fat. Maybe just a light spray of olive or canola oil?