Received: 23 April 2021
Accepted: 18 June 2021
First Online: 30 June 2021
: The study was conducted according to the guidelines of the Declaration of Helsinki. The ethical approval to conduct the NHANES was granted by the National Center for Health Statistics Research Ethics Review (#98–12; Protocol #2005–06; Continuation of Protocol #2005–06; Protocol #2011–17; Continuation of Protocol #2011–17; Protocol #2018–01). Informed consent was obtained from all participants.
: Not applicable.
: D.K., N.T., and V.S. declare no conflicts of interest. S.M.O. serves as a member of the Scientific Advisory Board on creatine in health and medicine (AlzChem LLC). S.M.O. owns patent “Sports Supplements Based on Liquid Creatine” at European Patent Office (WO2019150323 A1), and active patent application “Synergistic Creatine” at UK Intellectual Property Office (GB2012773.4). S.M.O. has served as a speaker at Abbott Nutrition, a consultant of Allied Beverages Adriatic and IMLEK, and an advisory board member for the University of Novi Sad School of Medicine, and has received research funding related to creatine from the Serbian Ministry of Education, Science, and Technological Development, Provincial Secretariat for Higher Education and Scientific Research, AlzChem GmbH, KW Pfannenschmidt GmbH, ThermoLife International LLC, and Monster Energy Company. S.M.O. is an employee of the University of Novi Sad and does not own stocks and shares in any organization. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.