Swetha Sivakumar, a food writer and researcher, is demystifying one ingredient every month, in a special HT column. This month: Ketchup. Did you know that ketchup has its origins in a fish sauce, was initially made in Europe using mushrooms and walnuts, and didn't involve any tomato? That's because the tomato was a nightshade fruit believed to be toxic. Watch the video to find out how the tomato lost its toxic tag. And watch as Sivakumar offers tips on how to pick the perfect ketchup for you and your family.