Mentioning heart disease usually conjures up images of older people, not young adults. But teenagers and people in their early 20s may also be at risk for heart disease, according to statistics and research from the American Heart Association.

By altering unhealthy behaviors early young people may be able to cut their chances of facing heart disease, now or ever, according to the AHA. Yet college campuses are bastions for the risky behaviors that can lead to potentially dangerous problems.

Cigarette smoking is a main risk factor that can increase the chance of heart disease, according to the AHA. Smokers have double the chance of a heart attack than nonsmokers and are more likely to die suddenly from one. The AHA estimates that about four million teenagers smoke. Across the nation, three-fourths of adult smokers began smoking before the age of 18, and an additional 15 percent began smoking before they turned 21.

Physical inactivity also adds to the danger of heart disease. The AHA reports that nearly half of all people ages 12 to 21 in the U.S. are not active on a regular basis. Regular exercise plays a large role in preventing heart and blood vessel disease, the association found.

Binge drinking, consuming large amounts of alcohol in a brief period, causes abnormal heart rhythms that can lead to sudden cardiac failure.

Other studies have shown that the risk of sudden cardiac death increases with heavy alcohol consumption, said Dr. Christine M. Albert, associate physician in the Preventive Medicine division at Brigham and Women’s Hospital and an instructor of medicine at Harvard Medical School. Our study found the risk began to increase at more than two drinks a day.

A Finnish study, published in the AHA scientific journal Stroke identified a Holiday Stroke Syndrome among women and young men. The study conducted with individuals age 16 to 60 found that stroke risk goes up during weekends and holidays.

Intake of more than 40 grams of ethanol (equal to about a one-ounce shot) during the preceding 24 hours associated significantly with weekend and holiday onset of stroke, said Dr. Matti Hillbom of the department of Neurology at Oulu University Hospital.

Other factors related to holiday stroke were smoking, gender, younger age and use of oral contraceptives. Researchers said that the holiday stroke syndrome may be one way to explain why apparently healthy young men and women can suffer a brain attack.

The risk of heart disease rises as the blood cholesterol level increases, and the AHA found that among individuals between 4 and 19 years of age, females have significantly higher cholesterol levels.

Some people are born with risk factors for heart disease. According to the AHA, men have a greater risk of heart attack than women. Men are also more likely to have attacks earlier in life. People of all ages with parents who have suffered heart disease are also more likely to develop it, the AHA found.