LEP and cancer: In a subgroup analysis conducted by cancer type, we obtained significant results that the LEP G19A polymorphism decreased the risk of colorectal cancer in one model (recessive model: OR = 0.816, p = 0.010); decreased the risk of esophageal cancer in two models (allele model: OR = 0.888, p = 0.014; dominant comparison: OR = 0.874, p = 0.022); and decreased the risk of other types of cancer in three models (allele comparison: OR = 0.866, p = 0.010; dominant comparison: OR = 0.842, p = 0.010; heterozygote comparison: OR = 0.849, p = 0.018) (Table 3 and Figure 2).