Staff

Joseph Nadglowski
President and Chief Executive Officer
Joseph Nadglowski is President and CEO of the Obesity Action Coalition. A frequent speaker and author on the importance of obesity awareness, Mr. Nadglowski has more than 25 years of experience working in patient advocacy, public policy and education and is a graduate of the University of Florida. As a patient advocate who has publicly shared his own personal experience with obesity as well as those of OAC’s members on many boards, taskforces, workgroups and public testimony, Mr. Nadglowski was recipient of the 2012 Society for the Study of the Alimentary Tract (SSAT) Public Service Award. As part of his advocacy work, he has dedicated a significant part of his work toward the recognition of weight bias, its impact on those with obesity and our nation’s efforts to combat it. He has been a guest of First Lady Michelle Obama at the White House to discuss childhood obesity and has testified before the Food and Drug Administration (FDA) on the importance of increasing treatment options for individuals affected by obesity.

James Zervios
Senior Vice President and Chief Operating Officer
James Zervios has more than 20 years of experience working in the nonprofit healthcare/patient advocacy sectors and is a graduate of the University of South Florida. James joined the OAC in 2005 and served many years overseeing the Marketing and Communications department until transitioning to VP/Chief of Staff in 2023. In March 2024, he was named Vice President and Chief Operating Officer of the organization. He is responsible for managing the organization’s operations, including overseeing all organization departments, corporate partner development, strategic planning, staff management, and speaking/presenting on behalf of the organization. In 2015, he was awarded the OAC’s Milestone Award for distinguished service to the organization.

Tracy Zvenyach, PhD, MS, RN
Vice President, Advocacy & Research
Dr. Tracy Zvenyach is the Vice President of Advocacy and Research at the Obesity Action Coalition. In this role, she provides leadership in the development and implementation of policy priorities and strategy for OAC and represents OAC in alliances and coalition efforts to advance obesity care. She also serves as an Adjunct Assistant Professor at Georgetown University, where she teaches healthcare policy and advocacy to graduate level students. In her previous roles, Dr. Zvenyach led obesity public policy and advocacy efforts for seven years at Novo Nordisk and worked in the U.S. Senate for years, on topics ranging from healthcare, women’s policy, workforce, disaster response, and judiciary policy. Two of her top legislative accomplishments include work on provisions included in the Affordable Care Act and reauthorization of the Violence Against Women Act. Dr. Zvenyach’s research and publications focus on health economics and policy research to address barriers to obesity care, as well as diet quality of pregnant women receiving the Women, Infants, and Children (WIC) supplemental food program. Dr. Zvenyach received a BS in nursing from the University of Wisconsin-Eau Claire and her MS in nursing and PhD in Health Policy from the University of Maryland-Baltimore. Dr. Zvenyach volunteers her time as Co-Chair of the Public Policy Council for the Wisconsin Nurses Association and President of the Board of Trustees of the Wisconsin Nurses Political Action Committee.

Lisa Gresco-White
Director of Membership and Development
Lisa Gresco-White has been with the OAC since 2007, where she has focused her efforts and passion on cultivating and strengthening member relations and partnerships. As the Director of Membership and Development, she works to grow and sustain OAC’s 85,000+ members through initiatives like the Sponsored Member Program and Corporate Council, while fostering an engaged community and mobilizing members for advocacy efforts. Lisa also leads the organization’s fundraising efforts, including individual giving, donor cultivation, planned giving, and programs such as the OAC Action Fund and Scholarship Program. With a strong emphasis on support, she also devotes her time to the creation of new and ongoing support opportunities for OAC’s members, along with the management of OAC’s volunteer base.

Michelle “Shelly” Vicari
Director of Programs
Michelle “Shelly” Vicari serves as Director of Programs at the Obesity Action Coalition. In this role, she leads the strategy, development and execution of OAC’s education, events and programmatic initiatives, including Weight Matters Magazine, the Your Weight Matters National and Regional in-person conventions, virtual conventions and a wide range of digital learning opportunities such as OAC’s Health Talks series and public awareness campaigns. Prior to joining the OAC staff in 2023, Shelly served on the OAC National Board of Directors for 10 years, bringing deep institutional knowledge and a strong commitment to the organization’s mission. She studied Child and Family Development and Political Science at Grossmont College and San Diego State University and brings her background in child development to the growth and evolution of Thrive Together, OAC’s Youth and Families Program, helping ensure programs are inclusive, supportive and rooted in lived experience.

Chris Gas
Senior Digital Media Manager
Chris joined the OAC in 2018 as the Web Development Manager within the marketing team. In his current role as the Senior Digital Media Manager, he leads the organization’s digital media strategies and emerging technology initiatives to optimize user engagement and organizational impact. He oversees the development and maintenance of OAC’s websites, ensuring performance, compliance, and brand alignment. Chris manages digital advertising, analytics, and video content creation while supporting cross-departmental initiatives in advocacy, programs, fundraising, and membership. He also coordinates the technology needs for live and virtual events and collaborates with external partners to enhance the OAC’s digital presence and public awareness efforts. Chris studied at Broward College and the Art Institute of Fort Lauderdale, focusing on web design and interactive media.

Sarah Bramblette, MSHL
Senior Advocacy Manager
Sarah Bramblette, MSHL is one of the newest additions to the OAC team. She brings with her decades of experience advocating for improved diagnosis, treatment, and insurance coverage for obesity, lymphedema, and lipedema. During her tenure as Board Chair of the Lymphedema Advocacy Group (LAG) she played an instrumental role in the passage and implementation of the Lymphedema Treatment Act, a federal bill that mandated Medicare coverage for lymphedema compression supplies. As Senior Advocacy Manager, Sarah utilizes her combination of personal experience and policy knowledge to lead OAC advocacy efforts. Prior to joining the OAC staff she had been an active member of the OAC since 2012. During that time she served on the National Board of Directors and chaired the Access to Care Committee. Sarah earned her Master of Science – Health Law from Nova Southeastern University in Fort Lauderdale, Florida.

Gianna Toto
Marketing and Communications Manager
Gianna Toto is the Marketing and Communications Manager at the Obesity Action Coalition. She joined the organization in 2025 as a Communications Coordinator. In her role, she supports the planning and execution of marketing and communications efforts across OAC’s channels, including social media, newsletters, blogs and other digital content. She also leads media pitching efforts to help amplify OAC’s voice and increase awareness of its mission. Gianna has a background in nonprofit communications and earned a degree in Communications in Technology with a minor in Marketing from the State University of New York College of Agriculture and Technology at Cobleskill.

Lynsie Nichols
Program Services Administrator
Lynsie Nichols is the Program Services Administrator at the Obesity Action Coalition. In this role, she is responsible for the coordination of OAC’s administrative activities working to ensure efficient and effective office operations. Areas of focus include: high-level support to OAC’s leadership with invoicing and assistance in the annual audits, management of OAC’s database amd fulfillment of information inquiries, resources and supply orders.

Rachel Davidson
Program Coordinator
Rachel Davidson is the Program Coordinator at the OAC, where she assists in managing programs, events, and initiatives that advance the organization’s mission to empower, educate, and support individuals affected by obesity. Passionate about patient advocacy, Rachel draws inspiration from her own experiences with obesity and is committed to making a difference. In her free time, she enjoys exploring her creativity through various projects, traveling to new places, and watching sports. She earned her bachelor’s degree in Child Development and Family Relations with a minor in Psychology from the University of Maine.

Alex Greco
Communications Coordinator 
Alex Greco is the Communications Coordinator at the Obesity Action Coalition. With eight years of experience in non-profit communications and international development, she assists with policy communications and advocacy efforts around expanding access to obesity care and combating weight-based stigma. Alex is a former education specialist with the Peace Corps in Ethiopia and has also served as an English and world literature teacher in the United States and Mongolia before transitioning to a career advocating for causes she’s passionate about. Alex earned her B.S. in English Education from the University of South Florida and an M.S. in Global Conflict and Human Security from the University of New Hampshire.

Emily Nelson
Communications Coordinator
Emily Nelson has nearly 10 years of experience working with non-profits and is a graduate of Brigham Young University – Hawaii. Emily joined the OAC in 2026 as part of the growing Marketing and Communications team. She is responsible for the corrdination of OAC’s communication pieces, which includes organizational newsletters, member emails, and more.

Contact Us

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