When the English were introduced to tomatoes they believed that they were poisonous. Since Americans at the time were British colonists we believed what the Brits believed. Perhaps it was a law.
Col. Robert G. Johnson, a lawyer from Salem, N.J. had traveled to Europe and had seen the tomato eaten. Later, back home, he ascended the courthouse steps with a basket of ripe tomatoes. The 2,000 citizens who gathered were certain that he was about to commit suicide. He began eating one, then another, as a band played dirge-like music. He did not, as his doctor predicted, "foam and froth at the mouth and bend over with appendicitis." From that day in 1820 to this day the tomato is a principal crop of Salem Country farmers. Americans finally began eating tomatoes about 1834.