Contrary to popular belief, humans may have begun evolving the ability to consume alcohol millions rather than thousands of years ago. In fact, research is finding that our ancient ancestors may have played a big role in allowing our bodies to take in and process alcohol. This ability allowed ancient humans to break down the alcohol that was present in rotting, fermented fruit on the forest floor, information which allows scientists to gauge when they began moving to life on the ground.
A study on the origins of human alcohol consumption
Matthew Carrigan and his colleagues conducted a study that focused on the genes that comprise a group of digestive enzymes called the ADH4 family to investigate how these genes evolved over time and allowed humans to metabolize ethanol after it is imbibed. These scientists looked at the ADH4 genes of 28 different mammals including 17 primates and collected the sequences of the ADH4 genes from genetic databanks or well-preserved tissue samples. They observed the ancestry of 28 species to see how closely related they were and calculated when their ancestors diverged, which resulted in the observation of over 70 million years of primate evolution. From there, researchers looked at how the ADH4 genes evolved over time.
To do this, Carrigan and his colleagues took the ADH4 genes from the 28 species along with the ancestral genes they had modeled and applied them into bacteria, which read the genes and manufactured the ADH4 enzymes. From there, they tested how well said enzymes broke down ethanol and other alcohols. Results showed that there was a single genetic mutation that coincided with a shift among human ancestors to a terrestrial life. This mutation allowed ancient humans to eat rotting, fermented fruit on the forest floor when other food was scarce. This did not mean that it was their first choice in food source, but rather that they had the ability to process the ethanol when fermenting fruit was all they had to consume.
Alcohol consumption in moderation
Carrigan and his colleagues were able to observe a time millions of years ago when humans were able to process and metabolize alcohol. However, even with this information, there is a warning. There were small benefits in small quantities, but not in excessive consumption. This is as true today as it was then. Today, moderate drinking can exhibit some benefits, but excessive alcohol intake can cause serious health problems including heart and liver disease or mental health problems. Moreover, these results support the idea that the attraction to alcohol became a problem when modern humans began intentionally fermenting food in order to generate more ethanol than would normally be found in nature, which is a possible precursor to what we know today as alcoholism or alcohol addiction.
Written by Brianna Gibbons, Sovereign Health Group writer