In the future, will we each have a digital bio-twin beside us, ready to whisper in our ear when our biometric data shows we’re at risk? Scientists say genes affect our lifespan by just 10 to 25 percent, making preventing illness key to extending our lives. Today, tech that quantifies our biophysical performance abounds, and more is on the way. But how should we protect our precious and private health information, while taking advantage of these powerful, possibly life-extending tools? And what can be done about the missing data of women, people of color and others historically ignored by medical research?