Weight gain aside, because that is a different variable, why do vegetarians have lower blood pressure? "Many people will say it’s because a plant-based diet is rich in potassium," Barnard said. "That seems to lower blood pressure. However, I think there’s a more important factor: viscosity, how thick your blood is."

Eating saturated fat has been linked to viscous blood and risk for high blood pressure, according to the World Health Organization, as compared to polyunsaturated fats. Barnard paints an image of bacon grease in a pan that cools and solidifies into a waxy solid. "Animal fat in your bloodstream has the same effect," he says. "If you’re eating animal fat, your blood is actually thicker and has a hard time circulating. So the heart has to push harder to get the blood to flow. If you’re not eating meat, your blood viscosity drops and your blood pressure drops. We think that’s the more important reason."

Unprompted and seemingly apropos of nothing, we move into one of my favorite topics, Thanksgiving.

"You know how on Thanksgiving everyone kind of dozes off? People say it’s the tryptophan in the turkey, but it’s not. It’s all the gravy and the grease that’s entered their bloodstream. It reduces the amount of oxygen that’s getting to their brain and they just fall asleep."

"That's terrifying."

That really is terrifying.