The Reinheitsgebot, also known as the 'German Beer Purity Law,' is one of the oldest food safety regulations in the world. Issued in Bavaria in 1516, it originally decreed that the only ingredients allowed in the production of beer were water, barley, and hops. Interestingly, yeast was not mentioned in the original text because its role in fermentation was not yet understood by science. The law was designed to protect citizens from cheap, potentially toxic additives and to ensure that valuable grains like wheat and rye were reserved for bakers to make bread. Today, while European Union regulations have relaxed some of these restrictions, many German breweries still pride themselves on following the Reinheitsgebot to ensure the quality and tradition of their lagers and ales.