Dr. Li is a Professor of Medicine, and Chief of Clinical Nutrition Division at UCLA School of Medicine, Ronald Regan Medical Center. She also directs the UCLA Center for Human Nutrition, overseeing the research coordinator, clinical dietitians, and clinical fellows. In addition, she is also the chairman of committee of NACSN, the vice chairman of committee of National Board of Physician Nutrition Specialists, and the Adjunct Professor of Peking Union Medical College Hospital. She has been a Principal Investigator for over 50 investigator-initiated and industry- sponsored clinical trials in the fields of nutrition, obesity and botanical research. She served as the Chair of Obesity Research Section at American Society of Nutrition. She also serves as a board member of UCLA Physician Practice Group.

Dr. Li is a board certified Internal Medicine and Nutrition Physician Specialist. She has published over 150 papers in peer reviewed journals such as JAMA, Annals of Internal Medicine, American Journal of Clinical Nutrition, Journal of American Dietetic Association, and Journal of Biological Chemistry etc. She was awarded the First Award of Young Investigators Forum in Los Angles by AHA, and the best physician in UCLA School of Medicine.