Appendix A - Dietary data collection and processing NI Report NDNS 2019-2023
Source: data.gov.uk (2025-10-10)

National Diet and Nutrition Survey 2017 to 2023 Report for Northern Ireland. This report presents results from 2017-2023 of the National Diet and Nutrition Survey (NDNS) for Northern Ireland. NDNS is a continuous cross-sectional survey, designed to assess the diet, nutrient intake and nutritional status of the general population aged 18 months and over living in private households in the UK.

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
 
 
Appendix A 
Dietary data collection and 
processing in National Diet and 
Nutrition Survey 2019 to 2023  
 
A.1 Introduction 
For years 1 to 11 (2008 to 2019) of NDNS, dietary data was collected over 4 consecutive 
days using a paper food diary with estimated portion sizes. From year 12 (2019), the survey 
moved to collecting 24-hour dietary recalls on non-consecutive days using Intake24, an 
online dietary data collection tool. This change was made to provide a more automated data 
collection method, compatible with new technologies and with potential to improve data 
quality, reduce costs and enable the survey to scale in the future. The introduction of 
Intake24 in NDNS represents a significant transition for the survey. A formal evaluation has 
been undertaken within NDNS to assess the impact of the method change on the survey 
data. See the stage 3 evaluation report for details.  
 
A.2 Food Diary 
Details of the food diary methodology used up to year 11 can be found in appendix A of the 
NDNS Years 9 to 11 report. In summary, participants were asked to keep a record in a paper 
food diary of everything eaten or drunk over 4 consecutive days. Food portion photographs 
were provided for a small number of frequently consumed foods but the majority of portion 
sizes were recorded by participants in household measures (for example 2 dessert spoons 
of baked beans, one Kit Kat (2 fingers) or, for packaged foods, the weight indicated on the 
packet). Foods and portions recorded in the diary were subsequently entered by trained 
coders into the dietary assessment system DINO (Diet In Nutrients Out). The linked food 
composition data came from respective years of NDNS Nutrient Databank (NDB) (see 
section A.5). 
 
A.3 Intake24 
Intake24 is an online automated 24-hour dietary recall tool based on the multiple pass 
method, primarily designed for self-completion (Rowland and others, 2018; Bradley and 
others, 2016). Intake24 was developed by Newcastle University, originally with funding from 
Food Standards Scotland and is licenced under the Open Government Licence. The tool is 
maintained and developed in collaboration between Cambridge University, Monash 
University (Australia) and Newcastle University (UK). The version of Intake24 used for NDNS 
years 12 to 15 (UK Locale, System Version 3, 2019) was provided and adapted by the 
University of Cambridge, based on the original, with technical advisory input from Newcastle 
University. A demo version of the Intake24 system is available.1 
 
Participants completing Intake24 are asked to record everything they ate and drank the 
previous day (midnight to midnight). Participants are guided through webpages in the 
 
1 The demo version of Intake24 is updated regularly and so may not be exactly the same as the version used in 
years 12 to 15. 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
following order: 
 
• meal based quick list (captures time, and lists foods) 
• detail pass (foods selected, portion details provided) 
• meal gap review  
• last chance review  
 
Pre-defined meal and snack times (for example breakfast at 08:00) are displayed in 
chronological order. However, the user can choose to complete entries in any order they 
wish, change the times and can delete or add more eating occasions. The multiple pass 
method means that foods and drinks are first entered as free text in the ‘quick list’ phase of 
the dietary recall to collect a list of all foods and drinks consumed during the previous 
day. The participant is then taken through the ‘quick list’ and for each item reported is asked 
to select from a list of potential matching food and drink names linked to a food composition 
code within Intake24. Participants can add, delete or change foods they have reported. Once 
a food or drink is selected, participants are presented with appropriate portion size 
estimation options. The majority of foods in Intake24 have a range of portion size photo 
images that the participant can review and select the image closest to the amount they 
consumed. If there is no photo, there is the option to report portion size as household 
measures such as individual items, different spoon sizes, or small, medium or large servings. 
Some foods offer both photos and household measures. For drinks, there are images of 
cups and glasses with a slider to indicate volume consumed or photos of bottles and cans.  
 
Intake24 includes a custom spell checker which works to correct both phonetic misspellings 
and typing errors in the free text. The system also prompts participants for items commonly 
consumed together (for example milk in tea or coffee, spread on toast), and prompts for 
missing foods and drinks if there are long time gaps between reported eating occasions or if 
only a few foods have been reported.  
 
Intake24 includes an embedded pre-coded food list. Participants are asked to select, as far 
as possible, their foods and drinks from the food list provided in Intake24. If they cannot find 
an exact match for the food consumed, the tool prompts them to choose the closest 
matching item where possible. If the participant still cannot find a suitable match for their 
food they can report this as a missing food. The missing food function asks the participant to 
provide information about the food for coding at a later stage (undertaken by the research 
staff based at the MRC Epidemiology Unit, University of Cambridge). 
 
After reporting each eating occasion, participants are asked to record where they had bought 
or obtained most of the food for that meal or snack in order to differentiate food and drink 
from the household grocery shop from that obtained from out of home sources such as 
restaurants and takeaways and ‘food on the go’. At the end of each dietary recall, questions 
prompt participants to record if their intake was typical for that day (and if not, the reason 
why), if they were following any special diet, the type of oil generally used for cooking (if any) 
and details of any dietary supplements taken.  
 
For children aged 10 years or younger, a parent or carer is asked to complete the dietary 
recall with input from the child as appropriate. Children aged 11 years and older could 
complete the recall themselves with details confirmed with others where necessary. If the 
dietary recall was completed by a proxy (parent or carer) there may have been occasions 
when they were unsure of the details of a particular food or an entire meal (such as for a 
child attending school). At the end of each dietary recall there is a question asking if the 
recall had been completed by a proxy (that is on the selected participant’s behalf) and, if yes, 
whether there were any difficulties. Any gaps in the recall could be noted here and taken into 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
account during the data checking process.   
 
At the end of the fourth completed dietary recall, Intake24 provides participants with the 
option to view on-screen dietary feedback. The feedback provides an averaged daily 
personal intake for selected foods and nutrients compiled from an average of the 
participant’s 4 dietary recalls combined (see appendix J). Participants who completed fewer 
than 4 recalls were not provided with feedback. 
 
A.3.1 Intake24 assistance  
 
During the initial interview (face-to-face or telephone), participants were asked to complete 
their first recall independently using Intake24. Interviewers then checked with participants if 
they had any problems completing their recall. In year 12 interviewers were asked to review 
the first recall before submission if possible. From year 13, this review moved to a check that 
face-to-face participants did not have any problems completing and submitting their recall. 
For those interviewed by telephone a follow-up phone call was scheduled. In the majority of 
cases, participants then went on to complete subsequent recalls independently with no 
further involvement from interviewers. 
For participants who were unable to complete their first recall independently, for example 
due to internet access issues or lack of confidence with technology, face-to-face recall 
assistance was offered by interviewers during in-home interviews. If a participant indicated 
that they were unable to complete the second recall independently, a follow-up visit was 
arranged whereby the interviewer scheduled a date and time to return to the household and 
complete the recall with the participant. At the end of each visit the participant indicated 
whether they could complete the following recall independently (so that some participants 
may have had assistance with the second recall but not the third and fourth).  
For remote interviews, or where internet access was poor in the area, telephone recall 
assistance was scheduled with research staff at the Epidemiology Unit. Participants were 
sent a printed food photograph atlas prior to the scheduled phone call to aid the estimation of 
portion sizes during completion of the recall. The researcher read out the instructions and 
prompts in Intake24 and the participant provided the information on their food and drink 
consumption. The researcher entered this into Intake24. At the end of the recall, the 
researcher arranged an appointment for the next dietary recall if assistance was still 
required. 
If all 4 dietary recalls were completed with assistance, the participant was sent a copy of 
their dietary feedback via email or post if they requested it. 
 
 
A.4 Dietary data processing 
Foods and portion sizes are assigned codes within Intake24, allowing the system to 
generate nutrient output at the individual item level for all foods and drinks reported. As with 
the coding of the paper diaries in NDNS, all foods within Intake24 were assigned nutrient 
composition data using the NDNS NDB (see section A.5.1). Prior to analysis, the raw 
Intake24 nutrient output was imported into a bespoke database to facilitate data checks and 
to assign foods reported as missing to an appropriate food code and portion size, using the 
original free text search term and missing food details provided by the participant. 
 
 
A.4.1 Quality checks 
 
Recall data were monitored according to a series of indicators of recall completeness. A 
number of thresholds were adopted for consideration informed by the research team’s 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
experience with processing and checking dietary data, and published studies using Intake24 
and other similar dietary assessment methodology. This included monitoring the number of 
recalls: 
 
• with 9 or fewer food items 
• with 3 or fewer eating or drinking occasions (occasions when a participant reported 
consuming only a drink without food were included in the count) 
• with completion time of under 3 minutes 
• where the energy (calorie) intake was very low (less than 400kcal) or very high (more 
than 4000kcal).  
 
These measures were not designed to classify recalls as complete or incomplete and recalls 
that met any of these criteria were not necessarily of poorer quality than recalls that did not. 
The purpose of the measures was to indicate where there may have been issues related to 
data collection that required further investigation and to provide a set of checks that could be 
used to assess the tool’s performance across the age groups and against other UK surveys 
using Intake24. Therefore, no recalls were excluded from the dataset on the basis of these 
checks alone.  
 
In addition to the basic counts, more detailed, manual checks were undertaken on a sub-set 
of 10% of recalls to identify instances of: 
 
• multiple food items in the participant’s search term (for example, ‘toast cereal 
yoghurt’) and only one food item was coded 
• inconsistencies between the search term and the food code selected, for example 
searched for chicken stir-fry but selected prawn stir-fry 
• ‘orphan’ foods (a reported food that appeared to have been eaten on its own, for 
example beef steak when it would commonly be eaten with other foods such as 
chips or salad)  
 
These checks were carried out on the year 12 data (October 2019 to March 2020) to assess 
how the new dietary data collection method was working in the survey, and on the first 4 
months of data collected in year 13 (October 2020 to February 2021) following the move to 
remote interviews (see appendix B). Undertaking and reporting on the above checks was 
part of the monitoring of Intake24 to identify potential issues and improvements for tool 
functionality and usability, for example additional food prompt questions, improved portion 
estimation and clarification around the naming of foods. These changes were implemented 
at intervals during NDNS years 12 to 15 data collection. No adjustments were made to the 
dietary data itself as a result of the 10% checks as it was not possible to apply the checks 
and adjustments systematically to the overall NDNS dataset. It was considered that bias may 
have been introduced if selected adjustments had been made.  
 
In addition, when all missing foods had been coded, individual recalls were reviewed where 
the total energy intake was less than 400kcal and where the participant had not stated that 
they consumed ‘less than usual’, or that they were on a weight loss diet. As a result of this, 7 
recalls were considered ‘invalid’ and excluded from the final years 12 to 15 dataset. 
 
As with the QA and QC approach taken for NDNS years 1 to 11 dietary data, portion size 
boxplots were generated by NDNS standard sex and age groups (1.5 to 3 years, 4 to 10 
years, 11 to 18 years and 19 years and over) within each food group. Boxplots (otherwise 
known as box and whisker plots) show the distribution of data and identify any extreme 
outliers. Extreme outliers were identified from the boxplots as individual data points separate 
from the box and whiskers since they were more than 3 x IQR (Inter-quartile range: 75th 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
percentile to 25th percentile) from the nearest quartile for that intake (either the 25th or 75th 
percentile). These were examined on a case-by-case basis and reviewed in the context of 
the participant’s overall reported consumption. Extreme portion sizes that were considered to 
be implausible, and likely to be the result of errors in portion size selection, were adjusted. If 
there was an issue with the food code itself, this was changed. Adjustments were carried out 
in the bespoke dietary database by changing the portion code at the individual recall leveI.  
 
Finally, boxplots were generated by NDNS age group to identify any infeasible or extreme 
energy and nutrient intake values. Extreme intakes that were considered to be implausible 
and likely to be the result of errors in portion size selection were adjusted at the individual 
recall level. Some extreme intakes were due to food composition inaccuracies in the NDB 
and these were corrected. 
 
As a result of the extreme outlier checks for portion size, energy and nutrients, 0.2% of all 
food and drink entries in the final data set were adjusted. 
 
A.5 NDNS nutrient databank (NDB) 
 
Dietary data for NDNS is linked to food composition values in the NDNS NDB to produce 
estimates of nutrient intakes. The NDB is compiled with information from the UK 
Composition of Foods Integrated Dataset (CoFID) supplemented by manufacturers’ data 
gathered through food labels and web information and from the FSA Food Recipes 
Database. The NDB contains a range of food codes, including manufactured products, 
homemade recipe dishes and dietary supplements and is maintained by a programme of 
regular updates. 
 
 
A.5.1 Rationalisation of the NDNS NDB for Intake24 
 
Intake24 includes an embedded pre-coded food list linked to NDB food codes. Before 
Intake24 was introduced into NDNS in year 12 (2019), a major review and update of the food 
codes to be included within Intake24 was undertaken. The aim was to provide a food list for 
participants that was simple and usable while reflecting, as far as possible, the heterogeneity 
of the food supply in the UK. This included moving to more generic codes in the NDB to 
allow a single code to represent a range of similar foods. This review process also provided 
an opportunity to rationalise the NDB, which had grown unsystematically over many years to 
contain over 5,500 foods and drinks, to enable more efficient management of updates in 
future years of NDNS.  
 
Details of the NDB review and rationalisation have been published elsewhere 
(Amoutzopoulos and others, 2022). In summary, dietary intake data from the first 10 years 
(2008 to 2018) of the survey were examined to identify reported consumption rates 
(frequency and amount) for all 6098 foods included in the 2018 NDB. During the review, 
other factors were also taken into consideration including whether the product was still 
available on the market and variations between different brands and food preparations. All 
foods were then allocated to one of the following categories:  
 
RETAIN 
Foods that are frequently consumed and/or foods which are not 
necessarily reported frequently but are essential as they are not 
represented by other retained foods, for example, fortified or ‘free-
from’ foods or foods used as ingredients in recipes 
EXCLUDE 
Foods that have been coded only a few times or have not been 
used or are no longer available 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
REPRESENT 
Foods that could be represented by another food: similar foods that 
could be represented by a retained code, for example, canned crab 
represented by boiled crab 
 
Overall, the numbers of foods assigned to each category were: 
 
• RETAIN = 2331 (39%) 
• EXCLUDE = 1541 (26%) 
• REPRESENT = 2061 (35%) 
 
Following this approach, those food codes in the EXCLUDE and REPRESENT categories 
were decommissioned in the NDB (61% of codes). A number of new generic food codes 
(n=150) were created mainly for sandwiches and salads which during years 1 to 11 were 
coded as individual components with the paper diary method. This resulted in a final 
database of 2,481 foods with linked nutrient composition data. Following the rationalisation 
process, the updated NDB (version UK_NDB_pre1) was incorporated into Intake24 for the 
start of year 12 of NDNS in October 2019.  
 
 
A.5.2 Updates to the NDB for years 12 to 15 
 
For NDNS, a programme of ongoing updates and revisions are made to the NDB so that the 
databank is up-to-date and as far as possible, reflects the nutrient composition of the food 
supply for each survey year reported. In years 1 to 11 the NDB was updated and applied to 
the dietary data on an annual basis. With the move to Intake24 the programme of updates 
has moved to biennial. However, due to the work to update the NDB for the transition to 
Intake24, and impact of COVID-19 on survey fieldwork, there were 2 updates, initially for 
year 12 and then for years 13 to 15. 
 
Updating of the NDB may include the addition of new foods as well as revision of nutrient 
composition of existing foods, either at individual or food group level following a programme 
of reanalysis, or to take account of reformulation reported by manufacturers and changes in 
fortification practices. Therefore, the same foods may have a different composition for some 
nutrients in one year of NDNS compared with another year. Table A.1 lists the key updates 
applied over years 12 to 15. It should be noted that updates applied in one year apply to 
future years unless further changes are made.  
 
 
 
 
 
 
 
 
Table A.1 Updates to the NDB  
 
NDB 
name 
Fieldwork 
year 
Analytical data 
updates 
Reviews of 
manufacturers’ or label 
data by food group 
Other 
UK_NDB_
1.1 
Year 12 
(2019 to 
2020) 
Selected 
micronutrients in 
cows’ milk 
(riboflavin, 
Bacon and hama  
Baked beansa 
Bread and rollsa 
Breakfast cereals 
 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
vitamin B12, 
iodine) 
 
Butter and fat spreads 
Cheddar cheesea 
Savoury sauces, pickles, 
gravies and condimentsa 
Crisps and savoury snacks 
Pizza 
Sausages 
Soft drinks, not low calorie 
or diet 
Soupa 
Biscuits 
Yoghurt, fromage frais and 
other dairy desserts 
UK_NDB_
2 
Years 13 
to 15 
(2020 to 
2023) 
 
Bread and rollsa  
Breakfast cereals  
Buns, cakes and pastries 
Burgers and kebabs 
(takeaway burgers only) 
Commercial toddlers foods 
Dietary supplements 
Other milkd 
Pork and dishesb 
Ready mealsc 
Soft drinks, not low calorie 
or diet 
Soupa 
Yoghurt, fromage frais and 
other dairy desserts 
Micronutrients in wheat 
flour (non-wholemeal) 
a Only sodium values updated. 
b Not manufactured pork products or dishes. 
c Not a specific food group, food codes were identified across all food groups based on name. 
d Updates made to some plant based drinks and lactose free milks, and flavoured milk drinks. 
 
 
 
 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
A.5.3 Update to energy value for fibre 
 
The NDB uses the Atwater system to assign energy values to foods based on 4.0 kcal per 
gram for protein, 9.0 kcal per gram for fat, 3.75 kcal per gram for available carbohydrate 
(expressed as monosaccharide) and 7.0 kcal per gram for alcohol (Food Standards Agency 
2002). Historically, in the Atwater system, dietary fibre (considered unavailable 
carbohydrate) did not contribute to energy intakes. Analysis of published data on energy 
availability from fibre (measured using AOAC method) recommended that the system be 
modified by using 2.0 kcal per gram for fibre (FDA, 2016; FAO2003) Therefore this factor 
was applied retrospectively to the dietary data for years 12 to 15. This change has been 
made following the UK regulation  allowing for voluntary fibre content declaration on the 
nutrition label in alignment with EU Regulation No. 1169/2011 which also include the 
contribution of fibre to energy content using this factor 2.0 kcal per gram. In future, energy 
from fibre will be calculated within the NDB.  
 
 
A.6 Disaggregation of composite dishes 
In order to determine total intakes of fruit, vegetables, meats and fish, all foods containing 
any of these food types have been systematically disaggregated into their components (Fitt 
and others 2010). To enable monitoring of intakes of these foods against government 
guidelines, it is important to quantify amounts eaten as part of composite dishes, as well as 
their discrete portions, to provide more accurate estimates of total amounts consumed at an 
individual food level. For example, carrots may be eaten as an accompaniment to a main 
meal, but they may also be consumed as an ingredient within a stew, together with 
additional vegetables such as onions and celery. Disaggregated data allows the automated 
estimation of total intakes of fruit, vegetables, meat and fish in NDNS, including the 
contribution from composite dishes. 
 
A.6.1 Calculation of 5 A Day using disaggregated data 
 
One of the estimates required for NDNS reporting is the intake of fruit and vegetables, 
specifically how participants‘ intake compare to the government recommendations to eat 5 A 
Day. Information on the fruit and vegetable content of each disaggregated food code was 
used to calculate the number of portions of fruit and vegetables consumed for each 
participant aged 11 years and over, using a portion weight of 80 grams (150 grams for fruit 
juice). In line with the 5 A Day criteria, fruit juice and smoothies combined and pulses 
(including baked beans) were included in the calculation up to a maximum of one portion per 
day each. The calculations included the fruit and vegetable content of foods such as meat, 
fish, pasta, rice and egg dishes, pizza, breakfast cereals, yogurts and dairy desserts and 
soups. Puddings and fruit pies were also included as these can contain significant amounts of 
fruit. Other foods that fall into the ‘high fat or high sugars’ segment of the Eatwell Guide were 
excluded from the calculation on the grounds that healthy eating advice is to reduce 
consumption of foods in this group. Therefore, the fruit and vegetable content of the following 
NDNS food groups was excluded from the estimates: 
 
• soft drinks (35.1, 35.2, 35.3 and 36.1, 36.2, 36.3) 
• confectionery (33.1, 33.3) 
• buns, pastries, cakes (including fruit cake) and biscuits (5.1, 5.2, 5.3, 6.1) 
• sugar, preserves (including jam) and sweet spreads (32.1, 32.2, 32.3) 
• savoury snacks (29.1, 29.2) 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
• ice cream (11.1, 11.2, 11.3) 
 
Main and subsidiary NDNS food groups are listed in appendix R. The calculation of 5 A Day 
portions was carried out as follows: 
 
• daily consumption of fruit juice (from 100% fruit juice) and smoothies was capped at 
150g (1 portion) 
• daily consumption of baked beans and other pulses was limited to 80g (1 portion) 
• daily consumption (g) of dried fruit was multiplied by 3 to account for effects of drying2 
• daily consumption (g) of tomato puree was multiplied by 5 to account for 
effects of concentration3 
• total weight (g) of fruit and vegetables (including the weights of baked beans and 
other pulses, dried fruit and tomato puree, modified as above) was divided by 80 to 
arrive at the number of fruit and vegetable portions 
• total weight of fruit juice (from 100% fruit juice) and smoothies was divided 
by 150 to arrive at the number of portions of fruit juice and smoothies 
• the number of fruit and vegetable portions and the number of portions of fruit 
juice and smoothies were summed to give total 5 A Day portions consumed 
 
5 A Day portions were not calculated for children aged 10 years and younger as there is 
not a quantified portion size recommendation for younger children.  
 
References 
 
Amoutzopoulos, B.; Steer, T.; Roberts, C.; Collins, D.; Trigg, K.; Barratt, R.; Abraham, S.; 
Cole, D.J.; Mulligan, A.; Foreman, J.; Farooq, A.; Page, P. Rationalisation of the UK Nutrient 
Databank for Incorporation in a Web-Based Dietary Recall for Implementation in the UK 
National Diet and Nutrition Survey Rolling Programme. Nutrients 2022, 14, 4551. 
https://doi.org/10.3390/nu14214551 
 
Bradley J, Simpson E, Poliakov I and others. Comparison of INTAKE24 (an Online 24-h 
Dietary Recall Tool) with Interviewer-Led 24-h Recall in 11-24 Year-Old. Nutrients 2016. 
8(6): 358 (viewed 16 August 2021) 
 
Fitt E, Mak TN, Stephen AM, Prynne C, Roberts C, Swan G and Farron-Wilson M. (2010) 
Disaggregating composite food codes in the UK National Diet and Nutrition Survey food 
composition databank. Eur J Clin Nutr 64: S32-S36 
 
Food and Drug Administration. Revision of the Nutrition and Supplement Facts Label. US 
Federal Register 2016. Vol.81. No.103 
 
 
2 Dried fruit (g) is multiplied by 3 to ensure that it is comparable to non-dried fruit on the basis of their respective 
micronutrient contents 
3 Tomato puree (g) is multiplied by 5 to ensure that it is comparable to canned tomatoes on the basis of their 
respective carotene contents. For example, 10g tomato puree and 50g canned tomatoes would provide 
approximately the same amount of carotenes (178μg and 181μg respectively) 

National Diet and Nutrition Survey: 2019 to 2023 (years 12 to 15) 
 
 
Food and Agricultural Organization of the United Nations. Food Energy – Food energy – 
methods of analysis and conversion factors. Report of a Technical Workshop 2003. Rome: 
FAO Food and Nutrition Paper no. 77.  
Food Standards Agency (2002) McCance and Widdowson’s The Composition of Foods, 
Sixth summary edition. Cambridge: Royal Society of Chemistry   
 
Rowland, MK, Adamson AJ, Poliakov I, Bradley J, Simpson E, Olivier P, Foster E. Field 
Testing of the Use of Intake24 - An Online 24-Hour Dietary Recall 
system.  Nutrients 2018. 10: xx-xxxx-xxxx (viewed 16 August 2021)