Foster and Homeless Youth Food Security Act of 2017 This bill amends the Food and Nutrition Act of 2008 to modify certain Supplemental Nutrition Assistance Program (SNAP, formerly known as the food stamp program) eligibility requirements for foster care and homeless youth who are enrolled at least half-time in an institution of higher education. The bill applies to foster care individuals or homeless individuals who are over 17 and not over 26 years of age, and enrolled at least half-time in an institution of higher education. The bill exempts the individuals from: (1) certain eligibility disqualification rules that apply to students enrolled at least half-time in an institution of higher education, and (2) SNAP work requirements. If the individual is enrolled at least half-time in an institution of higher education that provides the individual with housing that lacks an individualized cooking facility, the bill also: (1) modifies the definition of "food" to permit SNAP benefits to be used for certain meals prepared and served by the institution, and (2) permits the individual to be treated as a separate household for the purpose of SNAP benefits.