Maryn McKenna is a journalist and author and has contributed to National Geographic. She is an expert in public health, global health, and food policy and also stars in the 2014 documentary 'Resistance'. She also gave a speech in 2015 as a part of TED 2015. Wikipedia*
On the C-SPAN Networks:
Maryn McKenna has one video in the C-SPAN Video Library; the first appearance was a 2012 Forum.