THURSDAY, Jan. 15, 2004 (HealthDayNews) -- Lab rats bred to prefer alcohol live longer and are healthier than those bred to avoid alcohol.
However, that unexpected finding may be due to an accidental characteristic that developed in the production of the breeding lines and bears further study, says study co-author David Sinclair, a senior researcher at Finland's National Public Health Institute.
The research appears in the January issue of Alcoholism: Clinical and Experimental Research.
Of course, the finding isn't an excuse for people fond of alcohol to up their consumption for longevity's sake, Sinclair adds.
"The obvious question that needs to be answered is whether this difference in longevity is just an accidental characteristic that developed in the production of the [alcohol-preferring and alcohol-avoiding] lines, or is it somehow tied to the genes controlling alcohol drinking," he says.
Sinclair's team looked at two groups of rats, including 194 bred to be "alcohol-preferring" -- called AA (for Alko, Alcohol) -- and 123 rats bred to be "alcohol-avoiding" -- called ANA (for Alko, Non Alcohol).
The animals were randomly assigned to receive either 12 percent alcohol or water from age three months to 24 months. Animals that died during the experiment as well as the survivors killed at the end of the study were autopsied.
A lifetime of alcohol consumption did not shorten the animals' lives, Sinclair's team found, regardless of whether they were bred to prefer or avoid alcohol. Gender did not affect results, either.
The alcohol-preferring rats lived longer and were healthier than the alcohol-avoiding rats. By the age of 24 months, the death rate among the alcohol-avoiding animals was 3.6 times higher than in the alcohol-preferring animals.
In previous studies, Sinclair's team had found no effects of long-term voluntary alcohol consumption on survival in alcohol-preferring rodents.
Sinclair says if the same differences in longevity can be found in other lines of animals bred to prefer or avoid alcohol, the results would probably not be accidental.
He stresses his study shouldn't be reason for people to consume large amounts of alcohol over the long term, as there is strong evidence chronic intake of large amounts of alcohol causes serious health problems.
But, he says, the finding may cause his peers to look at the field of alcohol research a bit differently.
"Recently I was at a conference in Russia where a researcher was talking about the ability some time in the future of eliminating genes that increase the risk of alcoholism," Sinclair says. "Our findings highlight the fact that such actions might have mixed effects. Those genes could well have beneficial effects," he says, perhaps protecting from alcoholism.
John Crabbe is director of the Portland Alcohol Research Center at the Portland VA Medical Center and a professor at Oregon Health Sciences University. He says that while the Sinclair study doesn't have any immediate application for humans, it might one day.
"Ultimately studies like this are going to help us understand why some people drink more than others," he says.
The best next scientific step, Crabbe agrees, is to study longevity differences in other lines of rodent models bred to prefer or avoid alcohol.
More information
For frequently asked questions about alcohol abuse and alcoholism, visit the National Institute on Alcohol Abuse and Alcoholism. For facts about alcohol, check with the U.S. Department of Health and Human Services.
