Dr. Liu's research focuses on the genetic basis of cardiometabolic diseases, covering fundamental research, clinical epidemiology, risk modeling, and interventions across various populations. For thirty years, his research group has worked in global health, establishing numerous collaborative projects in different communities worldwide. His lab has identified multiple genetic and biochemical markers, as well as gene-nutrient interactions related to diseases and health outcomes. This includes germ-line mutations in various genes and their interactions with dietary and environmental factors. By integrating genotypes and plasma phenotypes into risk prediction, his team was the first to demonstrate the causal role of SHBG in diabetes development and to validate its clinical usefulness in diverse populations, opening new avenues for early detection and risk management. Using biomarkers for dietary carbohydrates, his lab was among the first to introduce dietary glycemic load (GL) and confirm its clinical utility for glycemic regulation; they also provided the first prospective evidence linking high GL to increased cardiovascular risk. He has published over 500 research reports in leading biomedical journals, including some of the most frequently cited publications in medicine and nutrition. In 2015, he was recognized by Google Scholar as a scientist with an H-index over 100. At UCLA, Dr. Liu co-founded the Burroughs Wellcome Fund Inter-School Program in Metabolic Disease, which was then one of the few cross-disciplinary doctoral programs in the U.S. designed to train scientists capable of integrating population-based quantitative disciplines with laboratory sciences. Since 1998, he has directly mentored and supervised 123 undergraduate, graduate, and postdoctoral fellows. Dr. Liu is an elected fellow of several medical societies, including the American Heart Association (AHA) and the American Epidemiological Society (AES). He has also served as a consultant for various national and international agencies addressing issues in medicine, nutrition, and public health.