Global Dietary Database 2017: data availability and gaps on 54 major foods, beverages and nutrients among 5.6 million children and adults from 1220 surveys worldwide

Background We aimed to systematically identify, standardise and disseminate individual-level dietary intake surveys from up to 207 countries for 54 foods, beverages and nutrients, including subnational intakes by age, sex, education and urban/rural residence, from 1980 to 2015.Methods Between 2008–2011 and 2014–2020, the Global Dietary Database (GDD) project systematically searched for surveys assessing individual-level intake worldwide. We prioritised nationally or subnationally representative surveys using 24-hour recalls, Food-Frequency Questionnaires or short standardised questionnaires. Data were retrieved from websites or corresponding members as individual-level food group microdata or aggregate stratum-level data. Standardisation included quality assessment; data cleaning; categorising of foods and nutrients and their units; aggregation by demographic strata and energy adjustment.Results We standardised and incorporated 1220 surveys into the final GDD 2017 database, together represented 188 countries and 99.0% of the world’s population in 2015. 72.1% were nationally, 17.0% subnationally, and 10.9% community-level representative. 41.2% used Food-Frequency Questionnaires; 23.4%, 24-hour recalls; 15.8%, Demographic Health Survey questionnaires; 13.1%, biomarkers and 6.4%, household surveys. 73.9% of surveys included data on children; 52.2%, by urban and rural residence; and 30.2%, by education. Most surveys were in high-income countries, followed by sub-Saharan Africa and Asia. Most commonly ascertained foods were fruits (N=803 surveys), non-starchy vegetables (N=787) and sugar-sweetened beverages (N=440); and nutrients, sodium (N=343), energy (N=256), calcium (N=224) and fibre (N=200). Least available data were on iodine, vitamin A, plant protein, selenium, added sugar and animal protein.Conclusions This systematic search, retrieval and standardised effort provides the most comprehensive empirical evidence on dietary intakes across and within countries worldwide.