“…Smoking is the single biggest cause of cancer worldwide and is responsible for around a third of all cancer deaths (IARC, 2004;Sasco et al, 2004). Smoking significantly increases the risk of lung cancer, mouth cancer, bladder cancer, kidney cancer, oesophageal cancer, pancreatic cancer and stomach cancer (Brennan et al, 2000;Iodice et al, 2008;Johnson, 2001;Parkin et al, 2011). Alcohol consumption can significantly increase the risk of mouth cancer, liver cancer, oesophageal cancer, breast cancer, laryngeal cancer and colorectal cancer (Bagnardi et al, 2001;Blot, 1992;Key et al, 2006).…”