Role of dietary habits in the development of esophageal cancer in Assam, the north-eastern region of India.

The etiology of esophageal cancer remains largely unknown. In recent years, the role of dietary habits in the development of esophageal cancer has received much attention. Prevalence of esophageal cancer in Assam is highest among all the states of India. To identify the possible risk factors, a hospital-based case-control study was conducted with 502 cases and 1,004 controls. "Kalakhar," a unique and locally made food item, has emerged as a significant risk factor (odds ratio = 8.0, 95% confidence interval = 5.1-11.5, p < 0.001). Consumption of very spicy foods, hot foods and beverages, a diet containing high amounts of chili, and leftover food was positively associated with the risk of esophageal cancer. Green leafy vegetables and fruits were protective for esophageal cancer. The risk factors associated with consumption of locally prepared food items, e.g., kalakhar, and some dietary practices did not decrease, even after adjustments with different confounding factors. However, further studies are required to conclusively implicate these factors in causation of esophageal cancer.