Researchers who studied high-risk children with a family history of heart disease determined they could benefit from a daily dose of vitamins C and E. These two powerful antioxidants helped slow atherosclerosis (hardening of the arteries) in the children. The children were predisposed to having high levels of LDL (bad) cholesterol, which can increase the risk of heart attacks early in life.
Fifteen children and young adults between the ages of 9 and 20 with hyperlipidemia, (an excess of fats or lipids in the blood) were put on the National Cholesterol Education Program Step II diet for six months. Six weeks into the diet, they were randomly assigned to receive 500 mg of vitamin C and 400 IU of vitamin E or placebos.
Children receiving the vitamin supplements when tested had improved flow-mediated dilation (FMD) in their arteries. Healthy children have FMD ranges between 8 and 12%, whereas the at-risk children's FMD average at the start of the study was only 5.7%. With vitamin supplementation, it had improved to an average of 9.5%. This is significant because reduced FMD is an early indicator of heart disease.
Engler, M. et al. "Antioxidant Vitamins C and E Improve Endothelial Function in Children with Hyperlipidemia: Endothelial Assessment of Risk from Lipids in Youth (EARLY) Trial", Circulation, 2003; 108:1059-1063. http://circ.ahajournals.org/