No brainer: Alcohol's harmful impact on brain health — from cradle to grave
The relationship between alcohol consumption and depression is well established. Drinking increases depressive moods and people often turn to alcohol to temporarily relieve depression or numb their feelings.
Alcohol-related liver disease has increased across the majority of counties over the last five years, according to a new report from the Health Research Board.
Hospital data shows the greatest number of cases were in Dublin, Cork and Galway, with a 16% rise in hospitalisations in Cork between 2018 and 2022.
"There is a high level of alcohol use in Ireland and for many, hazardous drinking is commonplace," the report said, with at least three people a day dying from alcohol-related conditions.
Author of the report, HRB researcher Anne Doyle, said alcohol use decreased during 2020 and 2021 as a result of pub closures and other covid restrictions and that "drinking at home became the norm for many".
The report said per capita alcohol use of 10.2 litres — down on previous rates of about 11 litres, still places Ireland 11th out of 45 countries.
A recent report from the Mental Health Commission outlined the paucity of mental health services for children and adolescents accessing the Child and Adolescent Mental Health Services (Camhs), with evidence of poor risk identification and management and when serious risk was identified, evidence of poor to no response.
Psychologist and health science podcaster Kimberley Wilson discusses the impact of alcohol on brain health in her new book .
Here is the evidence.
The product of alcohol metabolism in the body is acetaldehyde, which is the main culprit for hangovers, but also increases neuroinflammation (harmful inflammation in the brain), oxidative stress and excitotoxicity (nerve damage from excessive activation).
Harm from alcohol consumption is associated with how often, how much and over what duration we have been drinking.
There is evidence of harm from alcohol right from the very start in the womb. According to research in Lancet Global Health, 60.4% of Irish women continue to drink when they are expecting a baby — six times the global average of one in 10.
"Ethanol easily crosses the placenta, entering foetal circulation at the same blood alcohol concentration as the mother’s. However, the foetus’s underdeveloped liver cannot process the alcohol efficiently, meaning that it remains in the body for a long time, increasing the opportunity to cause harm to fragile developing tissues," said Ms Wilson.
Alcohol is a teratogen, with the ability to cause birth defects in the developing foetus. It is no surprise, therefore, that Ireland has one of the highest rates of foetal alcohol spectrum disorder (FASD) at 6,000 cases per year.
FASD embraces a range of lifelong physical and neurological conditions affecting children born to mothers who drink during pregnancy that include behavioural problems, difficulties regulating emotions and impulse control as well as learning difficulties and impaired cognition.
Kimberley Wilson suggests adult concern about alcohol consumption usually centres around weight gain or the behavioural consequences of not being in control.
"However, what most people are generally not thinking about is the potential impact of their drinking on long-term brain health."
The most recent Healthy Ireland survey 2022 showed over a third (37%) of Irish adults aged 15 and over drink alcohol at least once a week with over a fifth (22%) of drinkers binge-drinking on a typical drinking occasion.
But the evidence shows binge drinking among adolescents and young adults is a particular concern because the brain is still maturing during this phase in life.
Alcohol can inhibit neurogenesis — the process by which new neurons are formed in the brain, which can potentially lead to long-term structural and functional changes in the adolescent brain.
In terms of mental health, not only do hangovers increase the likelihood of experiencing anxiety, but it is estimated that about 20-27% of people with social anxiety have problematic drinking behaviours and rely on alcohol to provide them with "Dutch courage".
The relationship between alcohol consumption and depression is well established. Drinking increases depressive moods and people often turn to alcohol to temporarily relieve depression or numb their feelings.
Excessive alcohol consumption in the middle years is one of 12 modifiable risk factors for dementia listed by the Lancet Commission (2018) — a third of which are diet or nutrition-related (diabetes, hypertension, adiposity and alcohol).
Heavy alcohol consumption is one of the key modifiable risk factors for young-onset dementia, which is dementia that emerges before the age of 65.
In one study of 57,000 instances of young-onset dementia, 39% were identified as alcohol-related brain damage. In older people, about 10-24% of dementia cases are understood to be alcohol-associated.
The Public Health (Alcohol) Act 2018 is a giant step towards addressing the negative impacts of consumption on public health, with a specific target of reducing alcohol consumption to 9.1 litres per annum, delaying initiation of consumption by children and reducing harms caused by misuse, and ensuring the supply and price of alcohol is regulated and controlled in order to minimise harm.
Positive measures implemented to date include structural separation, regulation of sports sponsorship, restriction on promotional activities and minimum unit pricing.
Most recently, regulations were signed in May to introduce comprehensive health labelling of alcohol products sold in Ireland — warning of risks of alcohol consumption while pregnant, liver disease and fatal cancers from alcohol consumption, with a three year lead- time to prepare for the change.
And legislation works. Minimum unit pricing has been shown to lead to a 13.4% drop in deaths caused directly by alcohol consumption and a 4.1% reduction in hospital admissions in Scotland since its introduction in 2018.
However, proposals from Justice Minister Helen McEntee last year to increase availability of alcohol though ]url=https://www.irishexaminer.com/opinion/commentanalysis/arid-41055944.html] longer licensing hours[/url] and more venues for the sale of alcohol, has the potential to negate all the really positive progress being made by the Department of Health in recent years towards altering the culture around alcohol in Ireland.
In a report published in May, the Sale of Alcohol Bill (2022): An analysis of costs and benefits, international alcohol expert Professor Tom Babor, warned Ireland’s Sale of Alcohol Bill will increase risks of alcohol related-disease, injuries, crime, public disorder, and domestic violence.
Chair of Alcohol Action Ireland, Professor Frank Murray agrees.
‘We should bear in mind the fact that other jurisdictions are rowing back on liberalisation of night-time economies. For example, Amsterdam is placing further restrictions on alcohol consumption and earlier closures for bars.
"Some districts in Amsterdam had found a 34% increase in ambulance attendances for alcohol-related injury where there had been a one-hour increase in opening hours of alcohol outlets, compared with other areas within the city."
The evidence for the impact of alcohol on brain health at all ages from the womb to the grave is becoming increasingly apparent. Focusing on the strength of the evidence is an important first step in the concentration of resources to attaining targets for alcohol consumption per capita and the improvement of services for both alcohol treatment and mental health.
- Dr Catherine Conlon is a public health doctor in Cork and former director of human health and nutrition at Safefood
