U.S. Government's Open Data: Data.gov
Government Sponsored Health Data: HealthData.gov
Google's Public Data Searchable Directory: Google.com/publicdata/directory
Github Listings: https://github.com/awesomedata/awesome-public-datasets
List compiled by Forbes Magazine: forbes.com/sites/bernardmarr/2016/02/12/big-data-35-brilliant-and-free-data-sources-for-2016
Data Set Directory of Social Determinants of Health
Inter-university Consortium for Political and Social Research
Comprehensive Health Data and Tools
CDC Behavioral Risk Factor Surveillance System
CDC Youth Risk Behavior Surveillance System