Why is booze so bad for your liver?
Usually When bar staff refuse to serve a customer it’s not that newsworthy. But when 19-year-old Gareth entered a bar in Belfast and ordered an alcoholic drink it set the headlines chattering.
Why? Because he had just come from a hospital across the road where had been diagnosed with liver failure, reportedly following a weekend binge-drinking session.
His family is now pushing for Gareth to receive a liver transplant, but to become eligible he has to abstain from alcohol for six months, and there are concerns he may not live that long.
Gareth’s case highlights the potentially catastrophic effects of dumping large quantities of alcohol into your system over a short period. Meanwhile, experts here are concerned at the rising tide of alcoholic liver disease in general, and warn that even moderate drinking every day can cause damage over time.
So just why is booze so bad for the liver? Because alcohol is a toxic substance that damages and kills cells, explains consultant surgeon Prof Oscar Traynor, who directs the National Liver Transplant Programme at St Vincent’s University Hospital.
“[Alcohol] cannot be stored in the body so it has to be broken down and eliminated. So it’s broken down into other substances – first to acetaldeyde and that in turn is broken down to acetate. Both of those in turn are very toxic to many parts of the body, including the brain, the pancreas and the heart,” he says.
“But the liver gets particularly badly damaged because that’s the part of the body that actually breaks it down and handles it, that’s where the concentration is found.”
Several factors affect the extent of the liver damage, not least the quantity of alcohol being processed. Drinks differ in their percentage content of alcohol, but it’s the number of grams of alcohol in a drink that matters, rather than whether you are indulging in grape or grain, explains Traynor.
“Sometimes people think that whiskey is more damaging to your liver than beer or that red wine is more damaging than white wine – that’s a myth, it’s the amount of alcohol that causes the problem,” he says.
Current guidelines recommend no more than 14 units per week for a woman and 21 per week for a man, where a unit is one glass of wine, a half-pint of beer or a standard measure of spirit.
“They are not large amounts of alcohol – 14 units for a woman is two glasses of wine for each day, that’s less than half a bottle,” says Traynor. “And there are many couples in Ireland who would open a bottle of wine every night at home for dinner and drink the bottle between them. If you do that over 25 to 30 years you will do damage to your liver, there is no doubt.”
The pattern of drinking also has an impact. “If someone drinks a bottle-and-a-half of whiskey in 24 hours it could cause immediate damage to the liver that could actually kill them,” says Traynor. “But on the other side of it, if you take two units of those 14 units every day you are more likely to do damage than if you spread it over two or three days. So it’s recommended that everyone should have at least two alcohol-free days per week.”
Just how much alcohol abuse leads to cirrhosis, or permanent and irreversible liver damage, is hard to tell because people’s tolerances differ, according to Traynor.
“Females are more prone than males,” he notes. “And there’s an individual genetic predisposition – in some individuals their liver has certain enzymes that make them more resistant to developing cirrhosis than others.”
General nutrition has a role, too, adds Traynor. “The alcoholics who don’t eat proper meals, who get all their calories from alcohol, are much more prone to get cirrhosis than someone who drinks with a nice meal every day.”
But whatever the individual circumstances, as a nation Ireland has seen a surge in cases of alcoholic liver disease over the past 10 to 15 years, in line with most western European countries except France, where government-sponsored advertising campaigns have reversed the trend, according to Traynor.
Discharge data from acute hospitals in Ireland cite 705 diagnosed cases of alcoholic liver disease in 1995, jumping to 2,743 in 2006. That upward trend is borne out by a hike in referrals for the condition to the transplant programme, which currently carries out about 60 liver transplants each year (although by no means all for alcohol-related damage) – up from about 20 in the mid-1990s.
Donor livers are also showing signs of ill-effects, notes Traynor. “When we go out to retrieve an organ for a liver transplant, a lot more frequently now we are finding what we call fatty liver, which is the first stage of liver damage, and we cannot use these livers when they are very fatty. That’s something that we didn’t see when we started off 15 years ago.”
Meanwhile, we need to find better ways of treating alcohol-related liver damage, but research is sorely lacking at an international level despite the massive public health impact, according to consultant hepatologist Prof Aiden McCormick, also of St Vincent’s.
“This is something that the legislature should think about. There has to be some amount of the money that is taken in taxes from alcohol intake used to try to improve the treatment of end-stage alcoholic liver disease,” he says.
“Currently there is no mechanism at all for the money that is spent on booze in this country, not even a tiny fraction of it, to be spent on research to ameliorate the harm of alcoholic liver disease.”
source: Irish Times