BCS70: estimation of nutrient intake
Nutrient intakes from the 16 year dietary data were estimated as outlined by Crawley et al. [69]. It is notable that the procedures used to code this data were not supported by specially developed software as discussed in the NSHD section of this guide. Briefly, coding was completed using standard food portion sizes [70] from a list of 1250 foods.
McCance and Widdowson’s The composition of Foods 4th Edition was used as the nutrient database [40] along with additional information on the nutrient contents of other products as outlined by Crawley et al. [69].
There was no evidence of differences between weekday and weekend nutrient intakes and it was noted that many participants were revising for exams at home or were on holiday from school during the period of recording [69].
Nutrients from the sweep 10 (age 46 years) online diet diary were estimated automatically within the Oxford WebQ, [63] from McCance and Widdowson’s The Composition of Foods and its supplement reports [27, 41-43, 63, 71-75]. The processes for estimating nutrients from the Oxford WebQ have not yet been outlines for sweep 11 (age 51 years).