Humans generate a massive amount of health-related data. Health data streams ranging from personal fitness trackers and mobile apps to electronic medical records and fundamental, genomic, and clinical research are fed into sophisticated AI models, yielding clear insights and actionable knowledge about health status. Today, healthcare data is being mined for valuable insights. The healthcare industry now generates approximately 30% of all data generated globally. The total annual growth rate of data for healthcare will reach 36% by 2025. This is 6% to 12% faster than the manufacturing, finance, and entertainment industries. Healthcare data are complex, both structured and unstructured, and heterogeneous, originating from a variety of sources and distributed globally with global access. Generating insights from this fast-growing complex data is beyond human capabilities. The application of cognitive computing systems in health care is to bring together individual and clinical research, scientific research, and social data from a diverse range of healthcare sources to redefine a patient’s path to better health.