While network research often focuses on social integration as a predictor of health, a less-explored idea is that connections to dissimilar others may benefit well-being. As such, this study investigates whether network diversity is associated with changes in four health outcomes over a 3-year period of time in the United States. Specifically, we focus on how an underexplored measure of network diversity – educational attainment assortativity – is associated with common self-reported outcomes: propensity to exercise, body-mass index, mental health, and physical health. We extend prior research by conducting multilevel analyses using this measure of diversity while adjusting for a range of socio-demographic and network confounders. Data are drawn from a longitudinal probability sample of US adults (n=10,679) in which respondents reported information about themselves and eight possible alters during three yearly surveys (2013-2015). We find, first, that higher educational attainment is associated with more educationally insular networks, while less-educated adults have more educationally diverse networks. Results further suggest that having educationally similar networks is associated with higher BMI among the less-educated. Further exploration of the relationship between ego network diversity, tie strength, and health is warranted.