The American Butter Institute wants Congress to take action in making the Food and Drug Administration enforce laws that define butter as a dairy product. The organization sent letters to the leaders of the House Committee on Energy and Commerce and the Senate Committee on Health, urging them to compel FDA to enforce federal law against plant-based imposters that illegally misuse the term “butter” as a marketing trick. Butter’s definition has been settled law for more than a century, covered by legislation dating to 1886. Imitators made from vegetable oils have been able to use terms such as “margarine” and “spread,” ensuring a transparent marketplace. However, as butter’s popularity has grown in recent years, per-capita U.S. consumption last year reached its highest since 1968, the organization says marketing departments at brands such as Country Crock have been breaking the law by calling their products “plant-based butter.” The organization also supports the National Milk Producers Federation’s citizen seeking to address dairy imitators using dairy names.