7-d food diaries
Self-reported EI was assessed for all individuals using a web-based 7 d FD where participants recorded their food intake each day for 7 consecutive days. The 7 d FD guides respondents through six daily eating occasions (breakfast, morning snack, lunch, afternoon snack, dinner and evening snack). For the diet records, a database of 1340 beverages, food items and dishes was available, either through category browsing or through free text search, aided by a spellcheck application. It was also possible to type in foods not otherwise found through category browsing or a text search. The amount consumed was estimated by selecting the portion size from four different digital images among 320 photo series. The 7 d FD included internal checks for frequently forgotten foods (spreads, sugar, sauces, dressings, snacks, candy and beverages). Foods were reported as eaten on a generic level with no details of brand names, cooking method, types of fat used in cooking, etc. Standard recipes were used to estimate EI.If a participant failed to report for a day, they were reminded the next day by an e-mail. If this did not help, participants received a reminder phone call the day after.For participants to be included in the analyses, the7 d FD had to be completed for at least 4 d, including 1 weekend day to represent a weekly recording.For both methods, the EI was calculated for each individual with the use of the software system GIES (Version 1.000 i5 – 2014-09-10), developed at the NFI, Technical University of Denmark and the Danish Food Composition Databank Frida (version 3; Søborg, Denmark; 23-03-2018).