Many brain diseases don't start in the brain. Metabolic dysfunction, chronic inflammation, immune imbalance, and gut health all play a role in shaping brain health. When these systems become dysregulated, the effects Curiosity plays a key role in why I do what I do. I like to live on the edge of wonder, continually asking: Why do patients develop the problems they do? That Mark N. Perlmutter, MD Hand & Wrist Orthopedic Surgeon About David Perlmutter M.D.