Even as a young adult, being overweight may cause higher blood pressure and thicken heart muscle, setting the stage for heart disease later in life, according to new research in the American Heart Association’s journal Circulation.

The study is the first to explore if higher body mass index (BMI) results in adverse effects on the cardiovascular system in young adults.

“Our results support efforts to reduce body mass index to within a normal, healthy range from a young age to prevent later heart disease,” said Dr. Kaitlin H. Wade, lead author of the study and a research associate at the University of Bristol Medical School in the United Kingdom.

Researchers used data on several thousand healthy 17-year-olds and 21-year-olds who participated in the Avon Longitudinal Study of Parents and Children.

The researchers’ findings suggest that higher BMI:

• Caused higher systolic (top number) and diastolic (bottom number) blood pressure.

• Caused enlargement of the left ventricle, the heart’s main pumping chamber.

“Thickening of vessel walls is widely considered to be the first sign of atherosclerosis, a disease in which fatty plaques build up within the arteries and lead to heart disease. However, our findings suggest that higher BMIs cause changes in the heart structure of the young that may precede changes in blood vessels,” Dr. Wade said.