Rising mercury consumption from blue foods in China balanced by a shift to lower-mercury choices

Blue foods pose significant health risks as a primary dietary source of total mercury (THg) exposure for humans. Accurate meal-level THg content assessment that incorporates dietary preferences is essential to pinpoint major contributors to exposure. This study evaluated THg content and uncovered shifts in regional patterns of dietary choices across China from 2011 to 2019 by integrating THg concentration meta dataset, online recipe, household consumption data, and Internet user searching records. Results show that despite per capita THg consumption rose gradually due to rising blue food consumption, there was a national shift toward low-THg blue foods driven by increased shrimp and decreased high-THg fish consumption. Coastal regions exhibited the highest THg consumption due to greater blue food consumption while Northwest China displayed high-THg preferences with low overall consumption. While future dietary guidelines (EAT-Lancet, CDG) could increase THg intake in Northwest China by up to 7.1 times compared to 2019 levels, current dietary patterns and guidelines indicate that THg intake remains within safe health thresholds. This study provides a framework for meal-level Hg assessment to support safe, low-Hg blue food tailored recommendations regionally.