Food Frequency Information / Dietary Questionnaire for Epidemiology Studies
New variables in dietary output
The dietary analysis program has recently been updated to compute intakes of carotenoids, fatty acids, glycaemic load and dietary glycaemic index.
Variable descriptions are listed below: The nutrients from 'Energy' through to 'Zinc' are the standard output, and values are based on Australian nutrient composition data from NUTTAB95
(1) excepting folate and vitamin E, which were not available in NUTTAB, and have been derived from British tables.
(2) Within this is a variable 'BetaCarotene', which is ß-carotene equivalents (mcg/d) from NUTTAB. ß-carotene equivalents is the sum of the ß-carotene and half the amounts of carotene and and ß-cryptoxanthins present. Alpha-Carotene through to Lycopene are individual carotenoid intakes (mcg/d) calculated from the USDA data base.
(3) The value labelled Beta-Carotene is total ß-carotene, and is not related to the BetaCarotene from NUTTAB, although there is a mathematical relationship between the two. Because they come from completely separate databases at different times and countries, and different foods would have been averaged to get the different values to match with FFQ items, there is no expectation of close agreement. From FD40 to FD226N3N6, are intakes of individual fatty acids, based on a data set obtained from Neil Mann at RMIT, and now used in FoodWorks. Some of these will have very low or zero intakes, if it was in the original database we have retained the variable column. Glycaemic index and glycaemic load are based on values from an international table z.
(4) The method of calculation of these is explained in the paper with these tables, and also in a paper we published in Diabetes Care.
(5) The relevant section from the paper is copied below. 'Glycaemic index is a method of ranking foods on the basis of the blood glucose response to a given amount of carbohydrate from that food. GI values of individual food items were obtained from the 2002 International table of GI and GL values (4).
Where there was more than one value, GI values were averaged, with preference being given to Australian figures. Dietary GL was computed by summing the product of carbohydrate intake from each food by the GI for that food. GL was divided by total carbohydrate intake to obtain dietary GI, i.e an average of individual food GI values, weighted according to their contribution to carbohydrate intake (4). Alcoholic beverages were not included in the overall GI.' None of these new values have been tested or validated so we welcome any feedback and the values should be used with caution.
1. Lewis J, Milligan G, Hunt A: NUTTAB95 Nutrient Data Table for Use in Australia. Canberra, Australian Government Publishing Service, 1995 2. Holland B, Welch AA, Unwin ID, Buss DH, Paul AA, Southgate DAT: McCance and Widdowson's The Composition of Foods. Cambridge, Royal Society of Chemistry, 1993 3. USDA-NCC: USDA-NCC Carotenoid Database for U.S.Foods. 11th ed., 1998 4. Foster-Powell K, Holt HA, Brand-Miller JC: International tables of glycemic index and glycemic load values: 2002. Am J Clin Nutr 76:5-56, 2002 5. Hodge AM, English DR, O'Dea K, Giles GG: Glycemic index and dietary fiber and the risk of type 2 diabetes. Diabetes Care 27:2701-2706, 2004.