The Brussels sprout is a cultivar in the Gemmifera group of cabbages (Brassica oleracea), grown for its edible buds. The leafy green vegetables are typically 2.5–4 cm (0.98–1.6 in) in diameter and look like miniature cabbages. The Brussels sprout has long been popular in Brussels, Belgium, and may have originated there. Brussels sprouts, as with broccoli and other brassicas, contains sulforaphane, a chemical believed to have potent anticancer properties. Although boiling reduces the level of the anticancer compounds, steaming and stir frying do not result in significant loss.