The science of alcohol: How does it affect your liver and heart?

The science of alcohol: How does it affect your liver and heart?

Alcohol, the presumed panacea of low confidence, bad days in the office, and social cohesion, has built-up quite the reputation. The social drinkers, binge drinkers, occasional drinkers, and abstainers, after-all, all share an opinion on this 21 Century drug. Yet I am going to actively side-step these psycho-social issues and take you on a journey of a different kind. It begins with that infamous phrase, “Fancy a drink?”.

When the answer is “Yes”, the journey begins with your alcoholic drink slipping past your lips, down your oesophagus and into your stomach, dancing its way around your gastric juices. For those of you drinking a carbonated drink your alcohol will be absorbed faster as the pressure increases inside your stomach, forcing alcohol into your blood stream. This compared to the savvy consumer, who already has a stomach lined with food to curtail absorption. Soon, alcohol is absorbed into your blood stream. The portal vein, connecting your gut to your liver, acts as the super-highway transporting your alcohol, now neatly dissolved in your bloodstream.

At the liver, the Mecca of alcohol metabolism – alcohol meets its fate – where it becomes a mere shadow of its former self. The complex alcohol dehydrogenase enzyme pathway breaks down alcohol into safe bi-products of acetate, water and carbon dioxide with ruthless efficiency. Of course, there are limits. Too much alcohol can fast overwhelm your liver’s capacity to metabolise your liquid panacea, and consequently your blood alcohol level rises.

A rising level will have a plethora of effects. However, to give it a fair trial we need to consider both the short and long term. Now if I were the PR rep for alcohol I would highlight that the alcohol in your body (which is currently within safe, recommended limits) is relaxing, aiding social interaction, and even promoting cardiovascular disease prevention.

It relaxes you by travelling to your central nervous system where it depresses activity by interfering with chemical neurotransmitter signals, in particular, Gamma-Aminobutryric Acid (GABA). As your alcohol alters these, communication between your brain cells becomes increasingly impaired. We’ve all heard the phrase “I just didn’t know what I was thinking!” Now you have part of the answer!

Cardiovascular disease prevention from alcohol is, for many, a prickly chair to sit on, leaving them shifting, uncomfortable at the thought that a drug with such negative effects could be painted in such positive light. It is suggested that safe, moderated levels of alcohol promote your aforementioned relaxation which consequently improves your blood pressure – an established risk factor for vascular disease including heart attacks and strokes.

Of course, we are only human. Since your first alcoholic drink touched your lips, many more may have passed, with the assistance of friends, drinks deals, and a wave of excitable disinhibition as your central nervous system becomes increasingly impaired. Your blood alcohol level has now snuck past that happy and euphoric level of 10-30 milligrams per decilitre and you are now slurring your speech, with impaired balance (due to brain cerebellar dysfunction), and feeling sick. Vomiting, the hallmark of “I think I’ve had one too many” is triggered to get rid of your toxic, poisonous level of alcohol now achieved. Thank your stomach for this, whose lining has become too sharply irritated by the alcohol and on sending electrical signals to your vomiting centre in your brain, contracts sharply to produce a vomi