High Glycaemic Index Increases Risk of Lung Cancer, Study Finds

Rebecca Lewis March 10, 2016

Everyone knows that smoking causes lung cancer. In fact, it is the leading cause of the disease. But there are other factors that could raise your risk of this life-threatening illness. They include eating carbs. Yes. You read it right. It may sound a little weird but according to a new study, foods with a high glycaemic index (GI) - such as white bread or bagels, corn flakes and puffed rice - may increase the risk of lung cancer.

Foods that have high GI promotes a surge in blood sugar levels. In turn, it increases levels of a type of hormone called Insulin-Like Growth Factors (IGFs). Elevated levels of IGFs has been linked to a higher risk of lung cancer.

The study, led by University of Texas MD Anderson Cancer Centre, suggests that cutting out foods with high glycaemic index could reduce a person’s risk of developing lung cancer.

Findings also revealed that a related measure of carbohydrate quantity called ‘glycaemic load’ had no significant association with lung cancer risk. These suggest that the average quality, instead of quantity, of carbohydrates consumed that may modulate lung cancer risk.

While tobacco is the leading cause of lung cancer in the UK, it doesn’t account for all cases. There is a significant percentage of lung cancer patients who haven’t smoked.

The study, published in the journal Cancer Epidemiology, Biomarkers & Prevention, is the largest ever to investigate the association between lung cancer and glycaemic index. It is also the first to show that lung cancer risk in specific subgroups - including people who had never smoked and those with the sub-type squamous cell carcinoma.

The findings revealed that those who had never smoked, those with high GI were more than twice as likely to develop lung cancer. Meanwhile, among the smokers, high GI levels had 31 per cent higher risk of developing the disease than those who consumed foods with low GI.

In the UK, around 45,525 new cases of the disease are diagnosed each year, while 35,371 people lose their life to the disease annually, according to Cancer Research UK.

Previous research has shown that diet has a significant role to play in reducing the risk of lung cancer. Diets rich in vegetables and fruits reduce the risk of the disease while those that are high in red meat, saturated fats and dairy products are known to increase the lung cancer risk.