Can you hold your liquor?

• As an unessential element of our diets, the response that people can have to alcohol varies greatly.
• Some people have what is called “alcohol flush reaction” which basically means they feel the effects of alcohol more quickly than the average person.
• For those who have a certain defect in their ALDH2 gene, their metabolism cannot convert alcohol as easily or efficiently, which in turn causes them to get drunk on smaller amounts of alcohol.
• A study in 2015 found that people who carried a particular mutation in their serotonin receptor gene (HTR2B) were more likely to suffer from alcoholism or exhibit risky or aggressive behaviour when drunk.
• For those who know that they have a genetic predisposition to alcohol sensitivity, they can take steps to limit the effect that alcohol has on them.

Have you ever wondered why some people can drink all night with seemingly little effect, while others start getting tipsy halfway through their first glass of wine? Have you ever wondered why some people get really quiet when they drink, while other people try to start fights or dance on the table?

Gender and body mass play a role but so does DNA.

Unlike certain minerals and vitamins, our bodies do not require alcohol to survive. As an unessential element of our diets, the response that people can have to it varies greatly.

Some people have what is called “alcohol flush reaction” which basically means they feel the effects of alcohol more quickly than the average person. Symptoms of alcohol flush reaction can include accelerated intoxication, flushing of the face, and dizziness.

When we consume alcohol, our metabolism works to convert it into non-toxic compounds. The ability to do this, however, is determined in part by our genes. For those who have a certain defect in their ALDH2 gene, their metabolism cannot convert alcohol as easily or efficiently, which in turn causes them to get drunk on smaller amounts of alcohol. This defect of the ALDH2 gene can be found in as many as 58% of people of East Asian descent,^[i] whereas in other ethnic groups, this defect can be found in less than 1% of the population.

OTHER RESEARCH ON ALCOHOL SENSITIVITY

While ALDH2 is the major contributor to whether a person can or cannot hold their liquor, there may be other secondary genetic factors at play. A study in 2015 found that people who carried a particular mutation in their serotonin receptor gene (HTR2B) were more likely to suffer from alcoholism or exhibit risky or aggressive behaviour when drunk.^[ii]

According to the study, carriers of the mutation were not necessarily alcoholics, but they were more likely to lose control when drinking. Furthermore, those with the mutation were more likely to be impulsive even without the influence of alcohol.

HOW GENETIC TESTING CAN HELP

For those who know that they have a genetic predisposition to alcohol sensitivity, they can take steps to limit the effect that alcohol has on them. They may choose to limit their intake or abstain altogether. Those with a family history of alcoholism should be especially mindful that the problem could be genetic.

If you are sensitive to alcohol but do not wish to give it up completely, you can use precautions such as limiting your intake to a certain number of drinks per week, or alternating between alcoholic drinks and water etc. If you are going out, be sure to plan ahead and have a safe ride home.

AND IF ALCHOL SENSITIVITY ISN'T IN MY GENES?

Even if you are not genetically predisposed to alcohol sensitivity, it is important to use common sense when consuming it as overindulgence has been linked to a number of health problems including heart disease, certain types of cancer, and depression.^[iii]

Furthermore, while genetics is a factor in alcohol addiction, it only accounts for about 50% of the problem.^[iv] Other factors are related to environment such as work, relationships, and stress.

If you choose to drink, moderation is key as is taking the necessary preparations to stay safe.

References

[i] http://gnomad.broadinstitute.org/varian/12-112241766-G-A

[ii] http://www.nature.com/articles/tp2015170

[iii] https://www.ncbi.nim.nih.gov/pmc/articles/PMC4345133/

[iv] https://www.addictioncenter.com/alcohol/genetics-of-alcoholism/