• 

  Elizabeth Blackburn

  饰：Herself - Doctor, Molecular Biologist

• 

  Elissa Epel

  饰：Herself - Professor, University of California, San Francisco

• 

  Michael Marmot

  饰：Himself - University College Medical School, London

• 

  Bruce McEwen

  饰：Himself - Neuroendocrinologist

• 

  Jeff Ritterman

  饰：Himself - Cardiologist

• 

  Tessa Roseboom

  饰：Herself - Doctor, University of Amsterdam

• 

  Benjamin Sapolsky

  饰：Himself

• 

  Lisa Sapolsky

  饰：Herself - Neuropsychologist

• 

  Rachel Sapolsky

  饰：Herself

• 

  Robert Sapolsky

  饰：Himself - Neurobiologist, Stanford

• 

  Carol Shively

  饰：Herself - Doctor, Wake Forest University

• 

  Marcus Lovett

  饰：Narrator