A diet rich in starchy and sugary food has been considered the new culprit for increased lung cancer risk even if he or she doesn't smoke. Foods with a high glycemic index (GI) like white bread, rice, bagels and corn flakes should be avoided in order to reduce the risk of the disease.

GI is a term used to measure how the sugar in the blood increases after consuming a meal high in carbs, red meat and saturated fats. However, diets high in fruits and vegetables can decrease the risk.

Research published in the journal Cancer Epidemiology Biomarkers & Prevention shows the association between GI and lung cancer risk, including in those who have never smoked as well as those with squamous cell carcinoma (SCC), a subtype of lung cancer.

Carbs with High Glycemic Index Increase Lung Cancer Risk

In their study, lead author Dr. Stephani Melkonian of University of Texas MD Anderson Cancer Center found that there is a nearly 50 percent increased lung cancer risk among subjects with diets high in GI. Additionally, the risk in the group of smokers was 31 percent.

"Diets high in glycemic index result in higher levels of blood glucose and insulin, which promote perturbations in the insulin-like growth factors (IGFs)," Dr. Melkonian said, as reported by Telegraph. "Previous research suggests increased levels of IGFs are associated with increased lung cancer risk. However, the association between glycemic index and lung cancer risk was unclear."

To demonstrate the link between lung cancer risk and Gl, the researchers analyzed the data of nearly 2,000 diagnosed lung cancer patients and more than 2,400 healthy people. The subjects were surveyed regarding heir diet and health histories. The researchers measured their dietary GI and GL and divided them into five groups.

They found that in the group of never-smokers and non-smokers, the risk of lung cancer was doubly higher than the rest, especially if they had a high-glycemic diet.

IGFs Count is Higher in Lung Cancer Patients

While the study did not explain how glycemic index can increase lung cancer risk, the researchers say that previous research shows that IGF count is higher in lung cancer patients. NBC News notes that high GI foods can encourage the body to make more insulin via IGF, thus making tumors grow.

"Previous studies have investigated the association between glycemic index, and the related measure glycemic load, and a variety of cancers including colorectal, stomach, pancreas, endometrial, ovarian, prostate, and thyroid but these studies are limited and results have been largely inconclusive," the researchers wrote in the study.

The study showed that a healthy lifestyle, exercise and eating a healthy balanced diet can offset the chances of developing any type of cancer.