Funding for this research was provided by:
Carolina Population Center, University of North Carolina at Chapel Hill (5 R24 HD050924)
Foundation for the National Institutes of Health (R01-HD30880, DK056350, and R01-HD38700)
Fogarty International Center (5D43TW007709 and 5D43TW009077)
the National Key R&D program of China (2019YFC1605100)
Received: 13 December 2019
Accepted: 8 May 2020
First Online: 18 May 2020
Ethics approval and consent to participate
: The study was approved by the Institutional Review Boards of the University of North Carolina at Chapel Hill and the National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention. Each participant provided written informed consent (No. 201524).
: Not applicable.
: The authors have no conflict of interest to declare.