Human diets have been linked to about twenty percent of all cancers in developing countries(1). Diets have decisive roles as a protective or in the initiation and progression of chronic diseases(2, 3). Nutrients in the diets control the transcription factors that transform the gene expression while human genetic make can delineate susceptibility to diet-dependent health disorders(4).
Epidemiologic studies found strong significant associations between diets and esophageal cancer (EC)(5). Consumptions of red and processed meat, saturated fat, discretionary calorie in the highest category of intakes were significantly associated with increased risk of esophageal cancer (5, 6). Similarly, an elevated risk of EC was found among high-risk populations who consumed hot coffee, mate, tea, barbecued, and fried meat(7–12). The other dietary related practices associated with an increased risk of EC were eating salted fish, fried takeaway foods, food eating speed, and teeth loss (13, 14).
The associations between hot foods consumption patterns and risk of EC were not always consistent. The study in Sweden identified no significant association between drinking hot beverages and EC either independently or after adjusting for other causes(15). According to Wu et. al(2006) opinion, the oral cavity could adjust the heat so that the hot liquid foods temperature could fall too rapidly to cause injury to the esophageal mucosa(16).
Micronutrients and antioxidant substances are protective against esophageal cancer(17, 18). Previous studies discovered the strongest inverse relationships between the consumption of vitamins, beta carotene from raw fruits, dark green leafy, and cruciferous vegetables and esophageal carcinoma (19, 20). Likewise, an inverse significant relationship was found between higher dietary calcium intake and the risk of esophageal cancer(21).
Earlier studies in Africa revealed that the rise of EC incidences in endemic areas over the past decades were attributed to the consumption of crops that had degenerative effects(22). An increased risk was observed among populations that consumed maize (corn) and wheat-based staple foods compared to those who consumed diversified and nutritious foods (23). However, recent studies reported Polycyclic Aromatic Hydrocarbons(PAHs) emitted from partially combustible source fuels used for cooking foods, cooking places (24), consumption of hot foods as independent determinants of esophageal cancer among populations living in high-risk areas in Africa (10, 25–27).
Esophageal cancer is ranked 5th of all types of malignancies in Ethiopia following uterine, cervical, breast, and colorectal cancers(28). Arsi Zone is one of the EC endemic areas in Ethiopia(29). The findings regarding the dietary risk factors associated with an increased incidence of esophageal cancer were inconsistent. For example, in a small size pilot study, eating salty diets and inadequate vegetable intakes were identified as the independent predictors of risk of esophageal cancer(30). A case-control study by Magnesia et.al, (2005) documented eating Kocho (false banana) as the main dietary risk factors of EC opposite to a similar study by Shewaye(2016) which reported consumption of hot wheat porridge as the strongest predictor of the risk of esophageal carcinoma(31, 32). Furthermore, no study exists whether a fermented homemade traditional beverage that contains a high concentration of the carcinogenic chemical(acrylamide) would contribute to an increased risk of esophageal cancer(33). The present study was carried out to identify the dietary determinants of EC in the Arsi Zone.