By 1902, 32 states had imposed color constraints on margarine. Vermont, New Hampshire, and South Dakota all passed laws demanding that margarine be dyed an off-putting pink; other states proposed it be colored red, brown, or black. The “pink laws” were overturned by the Supreme Court (on the grounds that it’s illegal to enforce the adulteration of food) but the ban on yellow margarine remained. (The last hold-out, Wisconsin, only repealed its margarine-color law in 1967.)

In the cash-strapped days of the Depression and during the butter shortages of World War II, however, margarine inexorably began to bypass butter. This was helped along by improvements in the manufacturing process–margarine was now made from hydrogenated vegetable oils rather than animal fats–and by a clever side-step of the yellow ban in which white margarine was sold with an included capsule of yellow food coloring. Buyers simply squished the two together to produce a nicely butter-colored non-butter spread. (Though not in Wisconsin, where using yellow margarine was a crime, punishable by fines or imprisonment.) Eleanor Roosevelt (in New York) promoted it, claiming that she ate margarine on her toast. By the 1970s, Americans were eating about ten pounds of margarine per person per year.