Researchers in the U.S. say that those who start drinking alcohol in their early teens are more likely to suffer alcoholism later in life.

Information from a survey of 43,000 U.S. adults has further raised concerns that early alcohol use, independent of other risk factors, may contribute to the risk of developing future alcohol problems.

Those who begin drinking in their early teens are not only at greater risk of developing alcohol dependence at some point in their lives, but are also at greater risk of developing dependence more quickly and at younger ages, and of developing chronic, relapsing dependence.

Scientists at the Boston University School of Public Health and Youth Alcohol Prevention Center, led by Dr. Ralph Hingson, carried out a study using data from the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), of people aged 18 years and older.

The research questioned 43,000 adults about their use of alcohol and other lifestyle factors and found that for those who started drinking before age 14, 47 per cent had suffered alcohol dependence at some point during their lives.

This compared with only 9 per cent who began drinking at age 21 or over which is the legal drinking age in the U.S.

The study raises concerns particularly as research shows that growing numbers of young people are experimenting with alcohol.

The researchers dispute the commonly held belief that if teenagers are allowed to drink in their parents presence it will encourage responsible drinking in the future, and are warning that drinking alcohol at an early age may effect the developing brain and lead to dependence later on.

According to figures the amount of alcohol consumed by people under the age of 16 has more than doubled in a decade.

For each extra year before 21 that someone started drinking, it seems the greater the chance of developing alcohol dependence, regardless of other factors such as a family history of alcoholism, smoking and drug use.

A recently released 2005 Youth Risk Behavior Survey, conducted by the Centers for Disease Control and Prevention, found that among high school students nationwide, 26 percent had drunk alcohol (other than a few sips) for the first time before age 13.

Dr. Hingson says the study suggests that interventions that delay drinking onset may not only reduce the acute consequences of drinking among youth, but may help reduce alcohol dependence among adolescents and adults.

The research is published in the Archives of Paediatrics and Adolescent Medicine.