State laws that prohibit people under the age of 21 from buying or possessing alcohol, and from driving with any amount of alcohol in their system, save 732 lives each year in the United States, according to a study examining 23 years of research on the subject.

The study, appearing in the journal Alcoholism: Clinical and Experimental Research, also shows that an additional 165 lives would be saved if every state adopted 'use and lose' laws, which suspend the license of anyone younger than 21 who is cited for possession, consumption or attempt to buy alcohol.

"This study shows that raising the drinking age to 21 in all States was, and continues to be, a very effective measure," James C. Fell, first author of the report, noted in an email to Reuters Heath.

People who advocate lowering the minimum drinking age, Fell noted, contend that the positive effects of raising it to 21 only took place in the 1980s and has since lost its impact. But his study, spanning 23-years, shows the impact is "still strong, and is keeping the numbers of underage drinking and driving deaths down — more so than if the drinking age is lowered."

Fell and colleagues from the Pacific Institute for Research and Evaluation in Calverton, Maryland, looked at the impact of six underage drinking laws and four general impaired-driving and traffic safety laws for the period 1982 through 2004 and found that the most significant impact came from four underage drinking-and-driving laws.

The presence of the four underage drinking laws (i.e., possession, purchase, 'use and lose', and 'zero tolerance') was associated with "significant decreases" in fatal crashes, they report.

Moreover, Fell thinks the 14 states that do not have 'use and lose' laws "should seriously consider adopting them. Use and lose laws (where there is a driver's license sanction for an underage drinking violation) were associated with a significant 5 percent decrease in the rate of underage drinking drivers in fatal crashes and are currently saving an estimated 132 lives each year in the 36 States and the District of Columbia that have these laws."

The study also showed that three of the four more general laws that target all drivers also were effective in reducing drinking-driver crash deaths for all ages. These included laws that make it illegal to drive with a blood alcohol content (BAC) over .08; suspend a license for exceeding the .08 BAC while driving; and enable a police officer to pull over a driver who is not wearing a seatbelt.

Altogether, the results provide "substantial support for the effectiveness of under age 21 drinking laws and point to the importance of key underage drinking and traffic safety laws in efforts to reduce underage drinking-driver crashes," Fell and colleagues conclude.