Research consistently finds that health is stratified by race, ethnicity, and gender, and that romantic relationships, particularly marriage, are protective of health. Despite increasing prevalence of interracial and inter-ethnic relationships, few studies have investigated the association between partnership exogamy and health. In this dissertation, I examine whether and how heterosexual exogamy is associated with self-rated health, being overweight and obese, and depression. I additionally examine evidence for health selection into exogamous versus endogamous relationships and the evidence for health change over time in relationships. First, I use data from four panels of the Survey of Income and Program Participation, representing the adult population aged 18-59 in the US, to investigate partnership exogamy and self-rated health among Whites and nonwhites. I find that having a White partner is associated with better self-rated health for nonwhites, and that having a nonwhite partner is associated with worse health for White women. I find evidence that people in better health select into partnerships with Whites, and that having a White partner is associated with better self-rated health over time. Second, I use data from the National Longitudinal Study of Adolescent to Adult Health, representing young adults who came of age in the 1990s, to look at associations of partner race and ethnicity with being overweight and obese, and with depression. I find that overweight and obese White women select into new relationships with Black men, and also that having a Black partner is associated with weight gain over time for White women. Finally, I find that White young men and women who are more depressed are more likely to partner with nonwhite partners, and this effect is particularly strong for White women who have Black dating partners. I find evidence for depression increase over time among White women with Black partners, though the findings suggest a weaker causal impact of interracial relationships on depression than suggested by prior studies. To interpret the results throughout, I draw on gendered theories of interracial relationship formation including status exchange theory, and gendered theories of relationships and health that focus on stress and social status.