The carcinogenic transition: toxicological, metabolic, and microbiome consequences of Westernized high-heat culinary practices in Asian populations

Colorectal and prostate cancer incidence has risen rapidly in several industrializing Asian populations. Dietary-pattern explanations focus on macronutrients, but cooking method is rarely examined. We discuss a “carcinogenic transition” hypothesis, in which a shift from moist-heat cooking (≤100 °C) toward dry-heat techniques (≥150 °C) increases formation of heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) in food. We examine three components (the “Triple Threat” framework) that may be relevant to some populations: (1) dietary HCA/PAH exposure; (2) host variation in xenobiotic metabolism, including N-acetyltransferase 2 (NAT2), cytochrome P450 1A2 (CYP1A2), and aldehyde dehydrogenase 2 (ALDH2) variants, which may alter bioactivation or clearance; and (3) diet-associated gut microbiome activity, including β-glucuronidase (GUS)-mediated deconjugation of excreted metabolites, supported by in vitro data with unquantified human magnitude. The framework rests on epidemiological associations and experimental mechanisms, not established causation. Confounding by obesity, alcohol, screening, and acculturation cannot be excluded, and trials isolating cooking method are needed. We also discuss practical food-preparation strategies, including lower-temperature cooking and antioxidant-rich marinades. Support comes from food-chemistry experiments and small urinary biomarker studies; effects on cancer incidence remain untested.