By April Cashin-Garbutt, BA Hons (Cantab)
Where does the idea that alcohol kills brain cells come from?
Several origins have been suggested for the idea that alcohol kills brain cells. Some link it to the temperance movement, which called for prohibition of alcohol. (1, 2)
Another potential source of the idea is research into the number of brain cells of alcoholics and non-alcoholics. In 1990, Harper and Krill found that alcoholics had fewer brain cells than non-alcoholics. Consequently, some people began to think that alcohol causes the killing of brain cells. (3)
Does alcohol actually kill brain cells?
According to a recent article in Scientific American Mind, drinking alcohol does not kill brain cells although it can damage them. (4)
Specifically, it can damage the dendrites of neurons. Dendrites are specialized protrusions of neurons which bring information into the cell body. Thus, damaging the dendrites can cause problems in the relaying of information between brain cells. (4, 5)
This damage particularly occurs in the cerebellum, which is the part of the brain concerned with learning and motor coordination. (6)
According to Dr Petney, however, this damage is not permanent; yet it can cause changes in neuronal structure.
Dr Petney also stresses that losing entire brain cells isn’t necessary to disrupt brain function. In fact, brain cell damage will also have a disrupting effect. (7)
So, perhaps the question we should really be asking is not does alcohol kill brain cells, but what damage does drinking alcohol do to the brain?
Alcohol consumption and mental health problems
Alcohol consumption has been associated with mental health problems, such as anxiety or depression.
Moreover, more serious mental health problems, such as psychosis, can be caused by “extreme levels of drinking” which is defined as more than 30 units per day for several weeks.
Furthermore, stopping drinking alcohol can also be a problem for heavy drinkers as they may experience withdrawal symptoms associated with severe anxiety such as nervousness, tremors and palpitations. (10)
Chlordiazepoxide hydrochloride may be given to treat alcohol withdrawal. It is a medicine that helps people feel calmer, less agitated and less tense. (11)
Alcohol and brain damage
Alcohol has a severe dehydrating effect on the body. (8) In extreme cases the body may become so dehydrated that permanent damage is caused to the brain. This is one effect of a condition known as alcohol poisoning. (9)
Alcohol-related brain damage is also used to encompass several medical conditions related to alcohol consumption. These include alcohol-related dementia and Wernicke-Korsakoff syndrome. (12)
Alcohol consumption and risk of dementia
Binge drinking, also known as heavy episodic drinking, can lead to an increased risk of dementia. (13)
A recent study, however, found that only those who had a specific form of a certain gene, the apolipoprotein e4 allele, had an increased risk of dementia with the more alcohol they consumed. (14)
This means that those that did not carry the apolipoprotein e4 had similar dementia risks regardless of how much alcohol they drunk. (14)
Wernicke-Korsakoff syndrome is caused by a deficiency in thiamine, also known as vitamin B1. (15, 16) This deficiency is common to many alcoholics – up to 80%. (15)
Long-term alcohol consumption in fact can cause poor absorption and storage of thiamine. (17)
The condition starts out as Wernicke’s encephalopathy, which involves symptoms such as mental confusion, disturbances of the eye movements and an abnormal gait. (15)
If the condition is untreated, it may lead to Korsakoff syndrome, which is a psychiatric disorder involving dementia and psychosis. (17)
Can alcohol consumption improve brain performance?
Despite all the negative effects alcohol can have on brain cells, some research has shown that there may be positive effects of drinking alcohol on the brain!
A study published in the American Journal of Epidemiology reported that some aspects of cognition were associated with better function for those that consumed alcohol compared with those who consumed none at all.
The researchers did, however, state that this association was weakened when “social position” was added to the model, and they did not recommend that the findings be used to encourage increased alcohol consumption! (18)