Nadal received Bachelor's degrees in psychology and political science from the University of California, Irvine, a Master's degree in counseling from Michigan State University, as well as a Ph.D. in counseling psychology from Columbia University. During his time at Columbia, Nadal was mentored by psychologist Derald Wing Sue. He is currently a full professor at John Jay College of Criminal Justice and The Graduate Center, CUNY. From 2014 to 2017, Nadal was appointed as the Executive Director of CLAGS: the Center for LGBTQ Studies. From 2015 to 2017, Nadal became the president of the Asian American Psychological Association. In the organization, Nadal also co-founded the Division on Filipino Americans. Nadal is a national trustee of the Filipino American National Historical Society. Nadal's book Filipino American Psychology: A Handbook of Theory, Research, and Clinical Practice was noted for being the first comprehensive book on Filipino American mental health issues. Nadal has gone on to release other books on the topic. Nadal's research and writings concentrate on race, ethnicity, sexual orientation, gender, and the concept of racial microaggressions, and other microaggressions or subtle forms of discrimination towards racial/ethnic minorities, women, and LGBTQ populations. He created and published the Racial and Ethnic Microaggressions Scale in the Journal of Counseling Psychology in 2011. Nadal has also researched "sexual orientation microaggressions" In 2013, Nadal released That's So Gay!' Microaggressions and the Lesbian, Gay, Bisexual, and Transgender Community. In April 2015, Nadal received John Jay College's Scholarly Excellence Award. In October 2015, Nadal was named one of the Outstanding Filipino Americans of New York for his work in education and research.
Nadal has written or spoken about the need for Filipino Americans to address colorism within their families and communities, the need for people to challenge homophobia and transphobia, the experiences of invisibility and marginalization of Filipino Americans and other "brown Asians" in the general Asian American community, the racial microaggressions LGBTQ people of color experience in dating and sexual relationships, the systemic colorblindness and marginalization of people of color in queer studies, as well as anti-black racism. In 2007, Nadal gained attention with several media outlets when he started an online petition against ABC Studios for negative statements made about Philippine medical schools on the television show Desperate Housewives. In 2014, Nadal formed the LGBTQ Scholars of Color National Network as a way to provide support for LGBTQ people of color in academia. In 2016, Nadal and his colleagues wrote an open letter to the New York Times for their lack of Filipino American representation in a video segment that described Filipino American experiences. Nadal was also very vocal about addressing racism and Islamophobia in response to the Pulse tragedy in Orlando. In 2017, American Psychologist published Nadal's "Let's Get In Formation": On Becoming a Psychologist-Activist in the 21st Century, where he argued of the ethical responsibility for psychologists to "combat oppression on individual, interpersonal, group, and institutional levels."
