Dr. Heiman received a Ph.D. in 1978 from LSU School of Medicine with concentration in Physiology. He trained in neuroendocrinology during the next 4 years as a postdoctoral fellow at the IU School of Medicine and then returned to New Orleans to work with Dr. Andrew Schally (Nobel Laureate for defining Neuroendocrinology) at Tulane U School of Medicine. The next year he teamed with Dr. David Coy at Tulane to co-invented the drug Lanreotide, which is used to treat pituitary adenomas. Because of his expertise in the study of growth hormone secretion, he was recruited to Lilly Research Labs in 1987. Lilly initiated a research effort to discover drugs to treat obesity in 1994 and Mark accepted a role to develop a core metabolic physiology lab for the group. His lab was the first to demonstrate that leptin regulates energy balance by inhibiting neuropeptide-Y synthesis. His lab also developed the first validated RIA to measure leptin in humans and demonstrated the well known positive correlation of leptin levels with adipocity. The assay still serves as a gold standard, as do his assays to measure leptin in canine and rodent species. More recently, Mark’s lab was the first to demonstrate that ghrelin stimulates a positive energy balance. His research success was awarded with promotions to Lilly Research Fellow and he spent his final few years at Lilly as the Chief Scientific Officer (CSO) of Obesity Research. In 2014, Mark was awarded Fellow status in The Obesity Society for his research contributions that advanced the science of obesity.Mark retired from Lilly in 2009 and cofounded MicroBiome Therapeutics. As the CSO and Vice President of Research he discovered a gastrointestinal microbiome modulator to manage glucose intolerance in individuals with prediabetes and type 2 diabetes. Mark is also enjoying a role as the CSO of Scioto Biosciences committed to discovering solutions for Necrotizing Enterocolitis by modulating the neonatal GI microbiome.