A group of researchers made a dramatic and accidental discovery that a very tiny amount of ethanol is able to double the life expectancy of nematodes.
Nematodes or flatworms, about 1 mm in length, are often used in longevity experiments. Their cells can be counted, their genome is sequenced, and much of their intracellular proteome is understood.
Researchers at UCLA were attempting to study the effects of cholesterol administration on worm lifespan. To deliver the cholesterol into the worms’ feed medium, the scientists were dissolving it in a solution containing a very small fraction of ethanol, the same as drinking alcohol.
They accidentally discovered that the worms exposed to the ethanol lived to twice the expected lifespan and that it had nothing to do with the cholesterol. Normally the worms only live for 15 days, but the worms exposed to ethanol lived up to 40 days.
The concentrations however were extremely low, as little as 1 part per 20,000. This is equivalent to one teaspoon of alcohol in a bathtub of water, or one beer dissolved in 100 gallons of water.
Higher amounts of alcohol had no longevity effect, and large concentrations rapidly caused neurological damage and killed the worms.
The mechanism for how the miniscule amount of alcohol increased lifespan is not known, but the research group will be trying to answer that question in a follow up study. They hypothesize it acts either “serving as a carbon and energy source and/or by inducing a stress response.”
The significance of this research in humans is unknown.
Reference (PloS ONE)