US teenagers also show equal or lower rates of intoxication/binge drinking than do adolescents from most European countries, and most European countries report higher rates of intoxication and binge drinking for youth under 13.
  In 2009, the 21- to 24-year-old age group had the highest percentage of drivers in fatal crashes with blood-alcohol concentration (BAC) levels of .08 or higher – 35 percent.
 Any increase in traffic accidents or fatalities in 18- to 20-year-olds would be offset by a decrease for those 21 and older.
Drinking should be similarly restricted due to the responsibility required to self and others.
100 of the 102 analyses (98%) in a 2002 meta-study of the legal drinking age and traffic accidents found higher legal drinking ages associated with lower rates of traffic accidents.
Youth may choose not to drink, or to drink less often, because of decreased social acceptability or increased risks from parental or legal authorities.
Older youth and adults may furnish alcoholic beverages to minors less frequently, and licensed alcohol outlets may sell to minors less frequently, because of their perceptions that it is illegal, morally wrong, or because they might be caught.
 The National Highway Traffic Safety Administration (NHTSA) estimated that MLDA 21 decreased the number of fatal traffic accidents for 18- to 20-year-olds by 13% and saved approximately 27,052 lives from 1975-2008.
In 2009, the NHTSA found that the percentage of weekend nighttime drivers with a blood-alcohol concentration (BAC) of .08 or higher declined from 5.4% in 1986 (two years after the MLDA was raised to 21) to 2.2% in 2007.
Alcohol consumption can interfere with development of the young adult brain's frontal lobes, essential for functions such as emotional regulation, planning, and organization.