Obesity, Lung Cancer, and The Paradox of its Association: A Narrative Review

Abstract

Background: The obesity rate in Indonesia always increases every year. RISKESDAS (Indonesian National Health Research Data) 2007, 2013 and 2018 showed that obesity rate is always increasing in Indonesia. Lung cancer is the most common cancer in Indonesia which causes death.
 Objective: This review aims to explain various diseases which are associated with obesity, risk factors of lung cancer and the association between them.
 Methods: Literature search was conducted in pubmed and textbooks regarding obesity and lung cancer risk factors. The literature search on association between obesity and lung cancer was done in pubmed with the keyword "(Lung Cancer [Title]) AND (Obesity [Title])".
 Results: Based on the research conducted, it was found that obesity was associated with various diseases including type 2 diabetes, dyslipidemia, cancer risk, mood disorders, heart disease, hypertension, liver disease, and reproductive disorders. Furthermore, there are various risk factors for lung cancer, including gender, genetics, tobacco use, and exposure to toxic agents. The association between obesity and lung cancer is a paradoxical phenomenon that occurs, in which obese patients have a lower risk of developing lung cancer based on the meta-analysis research (RR: 0.79; 95% CI 0.73-0.85).
 Conclusion: Obesity can increase the risk of various diseases, and lung cancer which is one of the most common cancers in Indonesia also has various risk factors. However, current clinical research studies have shown that obesity actually reduces the risk of lung cancer. Thus we advise researchers around the world to further enhance experimental research either in clinical or laboratory about the body mechanisms that can explain this phenomenon. Regardless of this paradox association, we also suggest that the public should keep on controlling body weight because of the risk of various diseases associated with obesity.