The world’s largest food company is trying to show it can be environmentally sustainable and still make money. Activists are skeptical.

For today's edition of Dear Mark, I'm answering a bunch of questions from readers. The first one concerns another inflammatory marker, homocysteine. How could CRP be low but homocysteine be high? What could cause that? Next, I answer a barrage of kefir questions, including ones on kefir carb counts, pasteurized kefir, and water and coconut kefir. Finally, I address the elephant in the room: str...