Participants will receive a manipulated restaurant menu featuring salt warning labels next to menu items that are high in salt.

Participants will receive a standard restaurant menu (no labels).

A salt warning label will feature on the restaurant menu next to menu items that are high in salt (>3g, more than 50% of guideline daily amount [GDA] in the UK).

Participants will answer 3 PME questions using a Likert scale ranging from 1 - 5 anchored by "not at all" and "a great deal": Prompt: "Think back to the menu that you ordered from…" "The menu made me concerned about the health effects of consuming items high in salt", "The menu made consuming items high in salt seem unpleasant", "The menu discouraged me from wanting to consume items high in salt". The mean response to the three items will be calculated.

"Did you notice any warning labels next to any of the menu items when making your meal selection?" (yes/no).

If [yes], "What did the label tell you about?" Response options: Healthy items, Organic, Calcium, Sustainable, Added sugars, Vegetarian, Unhealthy items, Salt, Fibre, Gluten Free, None of these, Not sure.

If [yes], "Please describe what the label said" (open text response). Responses that mention high in salt or similar will be coded as aware.

"Did you think about the salt content of the meals when making your selection?" (yes/no)

For this question, both conditions will be shown an image of the labelled menu. "Did you learn something new from the salt labels on the menu?" (yes/no).

For this question, both conditions will be shown an image of the labelled menu, and some question phrasing is slightly altered.

"Did the salt label influence which food you ordered from the menu" (yes/no). "If [yes], how did the salt label influence your choice?" Response options: I avoided choosing a meal high in salt; I chose a meal high in salt; Other (free text response) Control: "Would the salt label have influenced what food you ordered from the menu?" (yes/no) If [yes], how would the salt label have influenced your choice? Response options: I would have avoided choosing a meal high in salt; I would have chosen a meal high in salt; Other (free text response)

Determined based on the total order of the participant, including food and drink. Prior to study commencement, all menu items will be sent for nutritional analysis to determine salt content/100g. Menu items will be weighed before being sent for analysis using kitchen scales (Vitafit VT706), so that specific salt content per serving can be calculated.

The "health" subsection of the Food Choice Questionnaire will be used to measure the extent to which health motives may influence participants' food choices. The subsection consists of 6 items, e.g. "It is important to me that the food I eat on a typical day….is nutritious" answered on a 4-point Likert scale ranging from "Not at all important" to "Very important". The mean response for the six items will be calculated.