The age that teens start drinking, smoking and doing drugs may be influenced by their gender and race, according to a recent study.

Researchers at Penn State University found that cigarette use among white teenagers is substantially higher than among black and Hispanic teenagers, especially at 18 years old.

Alcohol and marijuana use are also higher in white teenagers, and the numbers continue to increase until age 20. Throughout their 20s, blacks and Hispanics are more likely to pick up a cigarette-smoking habit, while the numbers start to decrease for whites.

"I think that the most important point is that there are big age-related differences in substance use by gender and race/ethnicity," researcher Rebecca J. Evans-Polce said in a statement. "In particular, African Americans show an increased prevalence in cigarette use much later than white adolescents. We need to think about tobacco prevention interventions that are targeted towards young adults, when use is increasing among African Americans, instead of just for younger adolescents."

For the study, researchers looked at four sets of data from the National Longitudinal Study of Adolescent Health, a survey conducted beginning in 1994, and repeated in 1996, 2001 and 2008 with the same individuals.

Evans-Polce and colleagues also found that use of alcohol was higher for males than for females during adolescence. Cigarette and marijuana use were similar between males and females, although slightly higher for male adolescents.

"Our research corroborated previous research showing differences in when individuals use substances depending on their race/ethnicity and gender," Evans-Polce said. "But seeing the large difference particularly in cigarette use by race/ethnicity was surprising and being able to see this all graphically really brought the point home in a novel way."

The findings are detailed in the journal Addictive Behaviors.