Green tea nondrinkers with both lower miR-29b and higher DNMT3B mRNA expression levels had a 3.23-fold (95% CI 1.55–6.72) increased risk of lung cancer, and this interaction of green tea consumption with miR-29b and DNMT3B mRNA expression was significant in lung cancer development (p < 0.001). Here, DNMT3B is linked to lung cancer.