Obesity and lung cancer are two important public health issues worldwide. We know that obesity is associated with the development and prognosis of many tumors, such as breast, colon, rectal, liver, gallbladder, pancreatic, kidney, and prostate cancers. Is there a correlation between obesity and lung cancer? There are few studies in this area. Recently, Rivera C’s team at the University of Paris Descartes in France conducted a study to assess the impact of obesity on the incidence of lung cancer and the safety and efficacy of oncologic treatments through the analysis of clinical and epidemiologic data, which was published online in Rev Pneumol Clin on February 10, 2015. The findings show that unlike other malignancies, obesity does not significantly contribute to the development of lung cancer. In contrast, patients with obese body mass lung cancer may bear a lower risk of death when treated. If a tumor patient is treated with conventional surgery, obesity can greatly increase the difficulty of preoperative anesthesia and prolong the operative time, but this does not increase postoperative morbidity and mortality. It is important to note that if chemotherapy or radiation therapy is used for obese tumor patients, the dose should be set with reference to the patient’s normal weight (normal weight based on height and other factors) rather than the actual weight of the “obese” patient. Interestingly, survival rates for obese patients with lung cancer treated surgically are higher compared to those treated non-surgically. In conclusion, although obesity is associated with many types of tumors, obesity is not associated with lung cancer. It is well known that oncology treatment is a long-term combined treatment process (surgery/radiotherapy/chemotherapy). During this period, obesity may have a positive effect on the outcome of lung cancer patients, perhaps the so-called “fat has its blessings”!