Over half of American workers are holding a paid job while also providing unpaid assistance and support to a family member. Research shows that family members who provide care to children or adults with special health care needs are themselves at risk of physical and mental health problems. Yet, little research has explored how the work environment mediates the effects of caregiving on caregivers' mental and physical health. With a sample of 2455 currently employed U.S. adults from the Work, Family, Community Nexus (WFCN) survey, a random-digit dial, nationally representative survey of Americans aged 18-69, we examine whether paid leave and flexibility policies mediate the relationship between caregiving and health. In Ordinary Least Squares regression models, we find that paid leave to address family members' health was associated with better mental health status as measured by the 5-item Mental Health Inventory and paid sick leave with better physical health status as measured by self-rated overall health status. A supportive supervisor was also associated with improvements in mental and physical health. For both men and women, paid leave and a supervisor's support offset some or all of the negative effects of caregiving, but for women, the buffering effects of working conditions are slightly larger. Enhancing the unpaid leave guaranteed in the U.S. Family and Medical Leave Act so that it is paid and passing national paid sick days legislation will help ensure that employed caregivers can retain their jobs, receive needed income, and meet their own mental and physical health needs.