Natural language processing technology can “read” texts written in social media or on chat helplines and find signals that alert doctors or counselors to a person who is threatened by cyberbullying or in imminent danger of directed self-harm. Heart attacks in women are often undiagnosed because their description of symptoms may not “present” as a heart attack, but NLP models can detect these incidents based on written doctor notes. In this talk, Dinakar presents his research findings from applying text understanding to five areas—online cyberbullying; online adolescent distress; crisis counseling on text hotlines; ways to model, predict and treat self-harm; and “cardiolinguistics” to model atypical angina in coronary heart disease. Results of this research impacts critical issues in military, medicine, crisis counseling, and beyond.