The aim of this study is to examine sodium intake and dietary sodium sources of 1-5-y-old children in a prospective, randomized long-term coronary heart disease prevention trial, focused on dietary fat modification. Counselling included no advice about reducing salt in the children's diets. Food consumption of 100 intervention children and 100 control children was recorded for 3 consecutive days at the age of 13 mo and for 4 consecutive days at the ages of 3 and 5 y. Sodium intakes were calculated using the Micro Nutrica program. Children's mean daily sodium (NaCl) consumption (intervention and control children combined) was 1600+/-527 mg (4.0+/-1.3 g), 1900+/-504 mg (4.8+/-1.3 g) and 2200+/-531 mg (5.5+/-1.3 g) at the ages of 13 mo and 3 and 5 y, respectively. The intervention children consumed as much or slightly more sodium than the control children at all ages studied. Half the sodium consumption was derived from added salt in commercially prepared or homemade foods. Milk, meat products, bread and cereals were other important sodium sources. In conclusion, nutrition counselling in the Special Turku Coronary Risk Factor Intervention Project (STRIP) trial, with its main focus on the quality of fat in child nutrition, has had minimal influence on children's sodium intake. To avoid excessive sodium intake in children, dietary counselling should include information about salt use, and food manufacturers should be encouraged to provide more low-sodium products.