Marmite (/ˈmɑːrmaɪt/ MAR-myte) is a British savoury food spread based on yeast extract, invented by the German scientist Justus von Liebig. It is made from by-products of beer brewing (lees) and is produced by the British company Unilever. Marmite is a vegan source of B vitamins, including supplemental vitamin B12. A traditional method of use is to spread it very thinly on buttered toast.