N08026: Calculation and collation of typical food portion sizes for adults aged 19 to 64 and older people aged 65 and over.
Thursday 14 October 2004
This research project will provide up-to-date information on typical food portion weights for adults, using information from dietary surveys and other sources.
Background
One of the aims of this research programme is to develop and improve methods for monitoring the amounts and types of foods consumed by the British population.
A weighed record is often regarded as the �gold standard� method for dietary assessment, but its use is not always appropriate or practical, not least because of its burden on survey participants. Other dietary assessment methods require the use of standard portion sizes or tools that provide estimates of portion size.
This project aims to produce an up-to-date set of typical food portion weights for adults and older people for use in dietary assessment.
The results from this project will update and extend the information on adult portion sizes published in 1993.
Research Approach
The project will extract and collate food portion size information from the National Diet and Nutrition Surveys of adults aged 19 to 64 years and people aged 65 years and over, allowing average food portion weights for different age groups to be determined. In addition, retail outlets, restaurant chains and food manufacturers will be contacted to obtain portion size information on packaged and fast foods. A list of typical food portion sizes for different age groups will be produced and tested using existing dietary survey data.
Results and findings
Background
A weighed record is often regarded as the ‘gold standard’ method for dietary assessment, but its use is not always appropriate or practical, not least because of its burden on survey participants. Other dietary assessment methods require the use of standard portion sizes or tools that provide estimates of portion size. This project aimed to produce a set of typical food portion weights for adults and older people for use in dietary assessment, updating and extending the information originally published in 1993.
Approach
Food portion size information from the National Diet and Nutrition Surveys (NDNS) of adults aged 19-64 years and people aged 65 years and over was extracted and collated and a list of typical portion weights was produced for each age group and tested using existing dietary survey data. Information on portion sizes from packaged and fast foods was obtained from retail outlets, restaurant chains and food manufacturers.
Results
Typical portion weights were calculated for over 700 different foods. Where significant age or gender differences were found in portion weights, separate weights were calculated for each age group, gender or both. These data will be used to help assess the diets of groups of adults and can be used as a guide for researchers devising dietary assessment tools in adults.
Detailed results
Portion weights were extracted from over 3400 weighed dietary records from the National Diet and Nutrition Surveys of adults aged 19-64 years and people aged 65 years and over. This included 400 records from older adults living in institutions. Similar foods were grouped into 751 food groupings. The foods reported in the final list covered all food groups including pasta, rice, pizza, bread, breakfast cereals, biscuits, cakes, puddings, milk (served in different forms) cheese, yogurt, eggs, meat, meat dishes, fish, vegetables, potatoes in different forms, fruit, savoury snacks, confectionery and beverages.
Statistical analyses were carried out on age and gender differences in portion weights, and, where significant differences were found, portion weights were calculated for each age group, gender or both. In addition separate portion sizes were calculated for older adults in institutions for over 200 foods where the portion size was significantly different from that for older adults living in their own homes.
The portion weights generated from the NDNS data were tested by using them to estimate energy and nutrient intakes from a sample of food diaries from other surveys and comparing the results with nutrient intakes calculated from the actual weights of food recorded in the diaries. There was generally good agreement between energy and nutrient intakes derived from the actual and calculated portion weights.
Portion weights collected for manufactured and fast foods included bread, biscuits, ready meals, burgers, sausages, meat pies, yogurts, savoury snacks, confectionery and soft drinks.
This project has provided updated information on typical portion weights for adults and new data on age/gender specific portion weights. These data will be used to help assess the diets of groups of adults and can be used as a guide for researchers devising dietary assessment tools in adults.