This review covers two ongoing studies in Finland: the Cardiovascular Risk in Young Finns study, which started in 1978, and the Special Turku Coronary Risk Factor Intervention Project for Children (STRIP), which started in 1989. In the cross-sectional Cardiovascular Risk in Young Finns study, cardiovascular risk factors were first assessed in 1980 in 3596 children and adolescents covering ages between 3 and 18 y at 3-y intervals. The latest follow-up examination was performed in 2001, when risk factors and early markers of atherosclerosis in carotid and brachial arteries were examined in 2264 subjects from the original cohorts, now covering ages from 24 to 39 y. The results clearly show that an individual's coronary heart disease (CHD) risk factor profile is regulated by early lifestyle-related factors and that exposure to risk factors in childhood induces changes in arteries that contribute to the development of atherosclerosis in adulthood. In the STRIP study, 1062 infants were randomized into an intervention group (n = 540; low-saturated-fat, low-cholesterol diet) or a control group (n = 522) at 7 mo of age. Fat, saturated fat and cholesterol intakes have been lower, while the polyunsaturated to saturated fat ratio has been higher in the intervention children than in the control children throughout the ongoing trial. During the first 7 y of life, serum cholesterol concentration was 0.2-0.3 mmol/l lower in the intervention boys than in the control boys, but the difference was negligible in girls. Neurological development of the intervention children at age 5 y was at least as good as that of the control children. Counselling had no effect on children's growth.