Patient Access to Medical Foods Act This bill provides for coverage of medical foods under Medicare, Medicaid, the Children's Health Insurance Program, and TRICARE. The bill also requires private health insurance providers to cover medical foods. Generally, a medical food is a food prescribed by a physician for the dietary management of a disease or condition. The bill expands this definition to include a food prescribed as a therapeutic option when a physician determines that traditional therapies are inappropriate for the patient. This definition shall apply to the insurance programs described above and to a federal grant program to encourage the development of drugs and medical foods for rare diseases.