This study evaluates the benefits of a first mile transit access program using shared mobility services. In doing so, the authors introduce a novel simulation and optimization framework that integrates macro-simulation of travel decisions to evaluate the mode choices for work and shopping trips. Specifically, to identify the potential demand shifts from drive alone mode to the proposed ridesharing and transit program. For the shifting individuals, a continuous location-allocation optimization model finds the optimal location of pick-up and drop-off (PUDOs) points where the ridesharing services picks-up the users and transports them to public transit stations. An agent-based simulation explicitly models the pick-up and transport activities. Finally, the framework evaluates the health benefits using the Integrated and Health Impacts Model (ITHIM). The framework allows estimating transit, travel, access, and waiting times, health impacts and costs. The results provide insights for planners and policy makers to better understand the system performance, recognize the gaps and provide solutions effectively.