Signposting is the same concept as traffic-light labelling: the front-of-pack system that uses red, amber, and green colours to signal at a glance whether a food is high, medium, or low in fat, saturated fat, sugar, and salt. Like road signs, the colours need no translation: green means go ahead, red means stop and think. Introduced to cut through the fine print of back-of-pack nutrition tables, signposting helps shoppers compare products in seconds and nudges manufacturers to reformulate away from reds. Critics argue it oversimplifies, penalising nutritious foods like cheese while flattering sugary cereals with added vitamins, but as a quick guide for busy shoppers it has proved one of the more effective labelling interventions.