Dr. T. Colin Campbell, PhD—vegan at 91—grew up on a dairy farm and went on to lead groundbreaking research examining links between dairy protein and cancer development. Dr. T. Colin Campbell’s work changed how many people think about diet and health — from The China Study’s large observational research to controlled lab experiments showing how animal protein (notably casein) can promote cancer in certain settings. Those findings raised the hypothesis that high animal‑protein (and specifically ca