This dissertation examines the influences of LGBTQ positive school climate and state-level anti-bullying policy with sexual and gender minority (SGM) identity enumeration on weight and victimization disparities among sexual minority adolescents. Compared to their heterosexual peers, sexual minority adolescents (those who identify as gay/lesbian or bisexual, or who are unsure of their sexual identity) have higher odds of having obesity and experiencing school violence victimization. The effects of school climate and anti-bullying policy that seek to specifically provide protections for LGBTQ adolescents on the health outcomes of obesity and school violence have rarely been examined, and especially in tandem. Decreasing disparities in both these outcomes would help improve quality of life and decrease morbidity. Therefore, the overall objective of this dissertation is to help fill several gaps in the literature related to obesity, school violence, school climate, and state-level anti-bullying policy with SGM identity enumeration. An adapted Social Ecological Model guided conceptualization and design of the three studies included. Chapter 1 introduces the current state of adolescent obesity, including trends in obesity over time, contextual influences on obesity, and obesity disparities among sexual minority adolescents. Existing research on school violence victimization, school climate, and SGM enumerated policy are also introduced and described. Chapter 2, a systematic review, aimed to systematically search and review the literature on the effects of positive school climate on weight-related health behaviors and risk factors for obesity. Overall, we found that LGBTQ adolescents in more positive school climates reported lower levels of bullying victimization, depressive and suicidal feelings, and sexual orientation-based harassment than those in less positive school climates. Results were more mixed for studies examining the effects of positive school climate on alcohol, tobacco, and other drug use. Chapter 3, a cross-sectional analysis of the Center for Disease Control and Prevention’s (CDC’s) Youth Risk Behavior Surveys (YRBS) and School Health Profiles (SHP) from 2010–2019, examined and compared the associations among sexual identity, school violence victimization, and obesity across varying levels of LGBTQ school climate in ten United States school districts. We found that for both female and male adolescents, regardless of sexual identity, those who reported two or more counts of school violence victimization had significantly higher odds of obesity compared to those who reported no violence victimization experienced in the last 12 months (1.33 and 1.24 greater odds, respectively). We also found that in the presence of more positive LGBTQ school climates, adolescents had 0.85 lower odds of obesity compared to those in the presence of less positive LGBTQ school climates. Chapter 4, a quasi-experimental difference-in-differences analysis of state-level anti-bullying policies and state-level CDC YRBS data from 1999–2019, examined the causal effect of anti-bullying policies with SGM identity enumeration on bullying and obesity trends over time. We found that adolescent girls had a significant 1.0 percentage point decrease in the probability of bullying victimization in the period post SGM enumeration enactment. For boys, this association was slightly stronger with a 3.2 percentage point decrease in the probability of bullying victimization in the post-period. However, when we examined subgroups of sexual minority adolescents specifically, we found the average treatment effects for SGM enumeration were even stronger for sexual minority girls and boys—with a 6.4 percentage point decrease in the probability of being bullied for sexual minority girls and a 6.0 percentage point decrease for sexual minority boys. Results for the obesity outcome showed that in the post-period, obesity rates increased for sexual minority girls and boys, an unintended effect that should be explored in future research that considers temporality of relationships among these outcome variables. Finally, Chapter 5 summarizes the studies included in the dissertation, identifies strengths and limitations, reviews key findings, and discusses implications for policy, practice, and future research. Using strong quantitative statistical methods, our primary contribution to the public health literature is that LGBTQ positive school climates and inclusive, SGM enumerated anti-bullying policies work to help decrease odds of obesity and rates of bullying victimization, respectively, for both heterosexual and sexual minority adolescents—highlighting how specific protections for one group of adolescents can extend benefits to all adolescents.