Carbohydrates, especially the refined white kind, have long been given a bad rap in the health stakes, but now the news is even worse.

A study has revealed that food with a high glycemic index - including bagels, white bread, cornflakes and short grain white rice, may not only be bad for your waistline, but can increase the risk of lung cancer too.

Researchers from the University of Texas say it is linked to the profound effect high GI foods have on the body.

The glycemic index is a measure of the quality of dietary carbohydrates, and how quickly blood sugar levels are raised after they are eaten.


Researchers say a high-GI diet triggers elevated levels of blood glucose and insulin which, in turn, increases levels of a type of hormone called Insulin-Like Growth Factors (IGFs). Higher amounts of IGFs have been linked with an increased risk of lung cancer.

Lead study author Dr Stephanie Melkonian said: "We observed a 49 per cent increased risk of lung cancer among subjects with the highest daily GI compared to those with the lowest daily GI."

The study suggests cutting out high GI foods can reduce a person's risk of developing lung cancer, but the amount of carbs consumed overall had no association with cancer rates. This means that when it comes to carbs, it's quality over quantity.

And while smoking is the leading cause of lung cancer throughout the world, what about those cases of non-smokers being affected by the disease?

In a surprising turn, scientists found non-smokers, who account for 12 per cent of those killed by the disease in the UK, appeared to be particularly at risk from a high GI diet.

The study revealed that GI was more specifically associated with lung cancer risk in specific subgroups - including people who had never smoked and those with the sub-type squamous cell carcinoma.

The new research, published in the journal Cancer Epidemiology, Biomarkers & Prevention looked at 1,905 patients newly diagnosed with lung cancer.

According to Ministry of Health data, lung cancer is the leading cause of cancer death in New Zealand, largely because it is often detected late.