Charles Brenner, University of Iowa (IMAGE) University of Iowa Health Care Caption Researchers led by Charles Brenner, PhD, professor and Roy J. Carver Chair of Biochemistry at the University of Iowa Carver College of Medicine, have conducted the first clinical trial of nicotinamide riboside (NR). The study shows that NR is safe for humans and increases levels of NAD+, a cell metabolite that is critical for cellular energy production and protection against stress and DNA damage. Credit Susan McClellen, University of Iowa Health Care Marketing and Communications Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.