Glycaemic index and glycaemic load in the diet of healthy schoolchildren: trends from 1990 to 2002, contribution of different carbohydrate sources and relationships to dietary quality

Abstract

Despite intense discussion of the glycaemic index (GI) and glycaemic load (GL) concepts, data on the GI or GL levels in the diet of children are scarce. The present analysis determined trends in the levels of GI or GL of healthy children from 1990 to 2002 and examined the contribution of carbohydrate (CHO) sources to the overall GL, and the relationships of the GI and GL to the overall dietary quality. The analysis includes three cohorts of participants from the Dortmund Nutritional and Anthropometrical Longitudinally Designed study, aged 7-8 years in 1990 (n 53), 1996 (n 46) and 2002 (n 56). A GI value was assigned to all CHO foods recorded over three consecutive days. In comparison with 1990, 7-8-year-old children in 2002 had slightly higher GI (56.5 v. 55.1 %; P=0.03) and GL (17.5 v. 16.7 g/MJ; P=0.04) levels. In all three time periods the combined contribution of the 'tolerated food groups' (i.e. sweets, soft drinks, cakes and cookies, and salty snacks) to the overall GL exceeded that of bread and rolls (1990, 31 v. 24 %; 1996, 29 v. 31 %; 2002, 28 v. 25 %). Conversely, rice and fried or mashed potatoes had only a minor impact. Children in the lowest GI tertile, but not those in the lowest GL tertile, had a better nutrient profile and a more favourable food choice. In conclusion, partial replacement of high-GI 'tolerated food groups' for low-GI foods would help to reverse the slight recent increases in GI and GL, and to improve the overall dietary quality of 7-8-year-old children.