Appendix 1 - AHS_ADG classification structure, serve sizes and inclusions
Appendix 2 - Additional information regarding the development of the ADG classification system
10 Grain (cereal) foods
The Grain (cereal) foods consist of two sub-groups: Wholegrains (or higher fibre) and Refined grains (or lower fibre). The ADG recommends consuming mostly wholegrain and/or high (cereal) fibre varieties of foods. The original modelling document (NHMRC, 2011) describes the inclusion criteria for wholegrain breakfast cereals as 'whole grain' (e.g. whole wheat), or contains ≥5 g fibre &
For the purpose of assessing the NNPAS food consumption data against the ADG and consistency with the ADG documentation and discretionary food flags, a cut-off of 30/35 g/100 g sugar was used in the primary analysis. FSANZ conducted an analysis to determine the potential degree of impact of using either cut-off. It was found that approximately 20% of breakfast cereals fell within the 20/25 - 30/35 g/100 g sugar range. Selection of different cut-offs would therefore make a difference to the analysis and findings of this project. As the NNPAS food classification system used the 20/25 g/100 g sugar cut-off when coding foods, users have the option of using either cut-off in their own data analysis.
20 Vegetables and legumes/beans
The original ADG modelling document divided the vegetable and legumes/beans category into five sub-groups as energy and nutrient content per serve is highly variable across this category (NHMRC, 2011). These sub-groups included green and brassica vegetables, orange vegetables, starchy vegetables, 'other' vegetables as well as legumes.
When developing the ADG classification system, the 'Other vegetable' group was further split into two sub-groups, 'Whole vegetables' and 'Vegetable juice' due to differing serve sizes. The 'Whole vegetable' group included all vegetables not specifically grouped by their family type (e.g. brassica) or distinguishing nutrient profile (e.g. pre-vitamin A present in orange vegetables). It was determined that marinated olives and other condiments vegetables such as pickled onions, gherkins, pickled ginger, capers and horseradish be classified in this group, however they would be flagged as discretionary as they are highly salted. The 'Vegetable juice' sub-group was included as 100% vegetable based juices were consumed in the NNPAS. The serve size of 130g used is the same as for fruit juices.
The original modelling document (NHMRC, 2011) indicated that orange sweet potato can be counted as either 'orange' or 'starchy', however, for this project, orange sweet potato was classified to only one category in the ADG classification system to avoid double counting when reporting at the two digit code level. Therefore, orange sweet potato was classified to 'Starchy vegetables' only as its starch content is comparable to other starchy vegetables and white sweet potato also falls in this category
Canned vegetables (e.g. tomatoes, beetroot) were classified as a serve of vegetables with no adjustment for liquid content as depicted in the ADG despite potential overestimation of the amount of vegetables consumed.
30 Fruit
This category was divided into three sub-groups due to differing serve sizes and included whole fresh fruit or canned fruit, fruit juice and dried fruit. Most of the NNPAS fruit codes were assigned directly to one of the ADG classification groups; however, all undrained canned fruit codes went to recipe. For fruit canned in natural juice, the whole fruit component was directly classified in the 'Fresh/canned fruit' sub-group and the natural juice component was directly classified in the 'Fruit juice' sub-group. Fruit juice concentrates were directly classified in the 'Fruit juice' sub-group with a conversion factor applied to dilute the concentration to a single strength juice as it would be when consumed.
40 Milk, yogurt, cheese and/or alternatives
The milks, yoghurt, cheese and/or alternatives category was divided into three sub-groups, namely higher fat, medium fat and lower fat dairy foods, which was the breakdown and naming used in the original ADG modelling document (NHMRC, 2011). This division was made as the ADGs recommend consuming mostly reduced fat varieties. The higher fat dairy foods sub-group consisted mainly of cheese and was defined as having a fat content above 10 g per 100 g; the medium fat dairy foods sub-group included predominantly regular milks and regular fat yoghurts with fat per serve ranging from 4 to10 g; and the lower fat dairy sub-group consisted mostly of reduced fat or skim milks or other dairy foods with less than 4 g fat per 100 g (NHMRC, 2011). Although regular fat milk and yoghurt also contain less than 4 g fat/100 g, the NHMRC modelling included them in the medium fat dairy group to reflect the recommendations to consume mostly reduced fat dairy products.
It was agreed that this classification would be retained when allocating NNPAS dairy foods to a sub-group, but that the cut-off values would be expressed on a per 100 g basis for all three sub-groups. The grouping of regular fat milk and yoghurt into the medium fat dairy sub-group was retained.
The dominance of this food group as a source of calcium in the diet meant that, although the group provides other nutrients, equivalence based on calcium was used to determine serve sizes (NHMRC, 2011). The ADGs state that dairy alternative products that have added calcium, such as calcium enriched soy or rice drinks, should contain at least 100 mg of calcium per 100 ml. Fortified milk alternative beverages that met this criterion were directly classified; however, unfortified or fortified beverages that did not meet this criterion were not directly classified and went to recipe.
The ADGs also lists several foods that are likely to contain a similar amount of calcium as a serve of milk, yoghurt or cheese. These include almonds with skin, sardines, canned pink salmon with bones and firm tofu. As these dairy alternatives do not fit with the classification of 'other dairy' on the basis of fat content and they are all classified elsewhere (e.g. nuts, fish, vegetables), it was decided not to include them as 'dairy alternatives'.
Although ice-cream, milk chocolate and the beverage base Milo (30% milk powder) are considered discretionary foods as they are not necessary for a healthy diet, it was decided they should go to recipe and not 'No classification', so that when there is an analysis including discretionary foods, the milk components from these foods are included as an ADG food (assigned to the ADG 'Milk, yogurt, cheese and/or alternatives' Food Group).
50 Lean meats and poultry, fish, eggs, tofu, nuts and seeds and legumes/beans
The ADGs makes the recommendation of enjoying 'lean meats and poultry', however, it does not provide a clear definition of what is 'lean meat'. During the development of the ADGs, food descriptors (e.g. lean, fully-trimmed, semi-trimmed, and untrimmed) were used to classify lean and non-lean red meat & poultry.
In the classification system for analysing the NNPAS data against the ADG it was necessary to split meat into lean and non-lean. Due to the unclear definition of lean in the ADG documents, it was decided that a 10% fat cut-off would be the most appropriate as it was a clear-cut off point and there was less ambiguities than using a food descriptor. In fact, a large proportion of meat cuts described as 'lean' or 'fully-trimmed' fell within the ≤10% fat cut-off, with fattier meat cuts (e.g. mutton, lamb chops, pork belly etc.) or those cuts described as 'semi-trimmed' or 'untrimmed' falling predominantly in the non-lean category (>10% fat).
Both red meat and poultry were classified by fat content in their raw form and that classification was then carried over to the cooked food codes. For example, if raw semi-trimmed T-bone steak had a fat content '5021 Unprocessed meat (' even if the fat content went slightly above 10% once cooked due to moisture loss.
While ham and trimmed bacon are technically lean and fall in the lean (
60 Water
The ADG's recommend drinking plenty of water. As the amount of water required varies depending on individual factors such as age, diet, climate and levels of physical activity, the ADG's do not indicate a specific serve size or a recommended number of serves or total volume per day. A standard serve size of 250 ml (1 cup) was used as a readily understood serve size. Based on the density of 1.0 for water, this was converted to a serve size of 250 g.
In the ADG classification system, 'water' includes municipal and unflavoured bottled water (NNPAS food sub-group codes 11701 and 11702). The amount of water in other beverages (e.g. tea, coffee, cordial) and water in other mixed dishes is derived from recipes and the corresponding amount of water in these mixed foods are included in the ADG database.
Analysis of water consumption can be done using the total volume of water as reported in the NNPAS using NNPAS classification codes, and/or using the water amounts from the ADG database. In the analysis for this project, a combination of reporting has been used. Table 2 illustrates the water components of beverages and the NNPAS classification codes included in the current analysis of water consumption. The main purpose of this breakdown was to put the consumption of water as a non-discretionary beverage (plain water and water component of non-discretionary beverage) into context as a proportion of total beverages or total moisture.
Consumption of water from one group of beverages where the ADG database was used was for 'Water from non-discretionary beverages'. This group included only the water proportion from the ADG database for non-discretionary beverages in NNPAS classification codes 111 (Tea), 112 (Coffee & coffee substitutes), 113 (Fruit and vegetable juices & drinks), 114 (Cordials), 115 (Soft drinks, and flavoured mineral waters), 116 (Electrolyte, energy and fortified drinks), 11703 (Purchased packaged water, fortified) and 118 (Other beverage flavourings and prepared beverages).
As the ADGs refer to 'drinking plenty of water', grams of water from the ADG database from non-discretionary beverages will be the only database values for water included in the analysis for this project. However, the database provides flexibility for users for other types of analysis, by including the grams of water component of discretionary beverages as well as non-beverage mixed foods. However, the water values are not complete for all foods in the database. One example is 'No classification' foods, that while they may contain water, will not have a water value in the ADG database. Therefore, caution should be used if trying to estimate total water consumption from the whole diet from the ADG database. It is recommended the database should not be used for that purpose.
It should also be noted that:
- when the analysis included both discretionary and non-discretionary beverage consumption amounts, the non-water component of the non-discretionary beverages in the food classification codes noted above, in addition to the total volume of the discretionary beverages in these codes were reported in summation with the total volume of the other remaining beverages not previously listed (milk and milk products, dairy substitutes and alcoholic beverages) as consumption of 'Remaining beverages';
- the 'water' component of the food from the ADG database is different to the 'Moisture' value for foods as reported in AUSNUT 2011-13, the nutrient database for the NNPAS. Moisture refers to the water content in foods and beverages. Variations in water content are important determinants of the levels of nutrient components, and data on water content make it possible to compare nutrient values (e.g. for different foods or different analyses of the same food) on a similar moisture basis.
Table 2. Water and water component of beverages and corresponding NNPAS classification codes included in the analysis of water consumption and total beverage consumption
|
Component
|
NNPAS Classification codes
|
What value for water was used for the analysis
|
|
Water consumption
|
|
|
|
(a) Municipal and unflavoured bottled water
|
11701- Domestic water (including tap, tank/rain water)
11702 - Purchased packaged water (including mineral water)
|
Total gram weight for water from NNPAS
|
|
(b) Water component from other non-discretionary beverages
|
111 -Tea
112 - Coffee and coffee substitutes
113 - Fruit and vegetable juices and drinks
114 - Cordials
115 - Soft drinks and flavoured mineral waters
116 - Electrolyte, energy and fortified drinks)
11703 - Purchased packaged water, fortified
118 - Other beverage flavourings and prepared beverages
|
Grams of the water component for non-discretionary beverages from the ADG database derived from recipes
|
|
Beverage consumption
|
|
|
|
(c) Remaining beverages
|
111, 112, 113, 114, 115, 116,11703, 118
|
Grams of 'non-water' components of non-discretionary beverages
(= total volume from NNPAS - water components from ADG database as in (b)) |
|
111, 112, 113, 114, 115, 116,11703, 118
|
Total gram weight of discretionary beverages from NNPAS
|
|
|
191 - Dairy milk (cow, sheep and goat)
198 - Flavoured milks and milkshakes
201 - Dairy milk substitutes, unflavoured
202 - Dairy milk substitutes, flavoured
29 - Alcoholic beverages
|
Total gram weight of both discretionary and non-discretionary beverages from NNPAS
|
|
|
(d) Total beverages
|
11, 191, 198, 201, 202, 29
|
Total gram weight of beverages from NNPAS
or (a) + (b) + (c)
|