(HealthDay) -- Teen girls who use birth control pills and teen boys who drink alcohol are at increased risk for elevated blood pressure, according to a new study.
The risk is also greater among teens of both sexes who have a high salt intake and those with a higher body mass index (BMI), which is a measure of body fat based on weight and height. High blood pressure (hypertension) increases the chances of heart disease and stroke.
Researchers looked at blood pressure, alcohol consumption, smoking, physical activity levels, prescription medicine use and eating habits among nearly 1,800 teens in Australia.
About 24 percent of the teens had pre-hypertension or hypertension, including 34 percent of those who were overweight and 38 percent of those who were obese.
Average systolic blood pressure (top number in a reading) among boys in the study was 9 mmHg higher than in girls in general. Among boys, systolic blood pressure was significantly associated with salt intake, alcohol consumption and BMI.
Regular physical activity was associated with lower diastolic (bottom number) blood pressure.
The use of birth control pills was significantly associated with higher blood pressure in girls. The average systolic blood pressure of girls who used birth control pills was 3.3 mmHg higher than in those who didn't use this form of contraception, and blood pressure was even higher in girls who used birth control pills and also had higher BMI readings.
Alcohol consumption did not affect blood pressure in girls, according to the study, which was published July 10 in the European Journal of Preventive Cardiology.
The major differences in blood pressure found between teens with healthy and less healthy lifestyles could have a significant impact on their risk for heart disease and stroke in adulthood, the researchers said.
"Adolescents need to be aware that a lifestyle which predisposes to fatness, high salt intake and alcohol consumption may lead to adverse health consequences in adult life. The effects are additive and already associated with hypertension. Moreover, teenage girls taking oral contraceptives should be advised about regular blood pressure monitoring," study author Dr. Chi Le-Ha, of the Royal Perth Hospital, said in a journal news release.
Explore further: Gender differences in blood pressure appears as early as adolescence
More information: The U.S. National Heart, Lung, and Blood Institute has more about high blood pressure.