Alcohol harms the liver by first breaking down gut protection, says study

Health risks of drinking alcohol: When you drink alcohol, it causes harm by weakening the gut’s natural defences and letting bacteria leak into the liver, where they fuel even more damage (Image: Pexels)

There’s a lot more that really happens in your body when you drink alcohol, apart from the hangover. You’ve all heard that alcohol is bad for your liver. But what’s now becoming clear is why it’s so bad. Turns out that the liver’s not even alcohol’s first target.

The trouble starts in your gut.

Researchers at the University of California San Diego have uncovered what they're calling a “hidden shortcut”, a way alcohol causes harm by weakening the gut’s natural defences and letting bacteria leak into the liver, where they fuel even more damage.

The gut-liver connect:

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Your gut is full of bacteria, mostly helpful, some harmful. Normally, a protein called mAChR4 helps keep them in check by maintaining gut barriers and teaching the immune system what to ignore and what to fight. But chronic alcohol use shuts down mAChR4, weakening the gut’s defenses. This allows bacteria to leak into the liver, adding to the damage already caused by alcohol. The result: inflammation, scarring, and liver disease.

In mice, restoring mAChR4 (with drugs in development) reduced liver damage by keeping gut bacteria in place. Surprisingly, mAChR4 is also found in brain regions linked to habit and addiction, and people with alcohol use disorder often have less of it there too. That means this protein, and the drugs that target it, could potentially treat both liver disease and alcohol addiction. A two-for-one breakthrough.

Most treatment options focus on treating the symptoms after the damage is already done. But this research points to something different: protecting the gut early on to stop liver damage before it starts. And because drugs that activate mAChR4 are already being tested for conditions like schizophrenia, there’s hope they could be fast-tracked for this use, too.

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Lead researcher Dr Cristina Llorente says, “We’re learning that the gut isn’t just along for the ride, it’s actually driving much of the damage we see in the liver. If we can fix that early leak in the system, we may be able to prevent the worst outcomes of alcohol use.”

Your gut is supposed to protect your liver. Alcohol breaks that protection. But now, scientists think they’ve found a way to rebuild it. And that could be a game-changer, not just for liver disease, but for the people struggling with alcohol itself.

FAQs on Health Risks of Drinking Alcohol

1. How does alcohol damage the liver?

Alcohol weakens gut defenses, allowing bacteria to leak into the liver. This leakage causes inflammation, scarring, and liver disease.

2. What is the gut-liver connection?

The gut contains bacteria that are usually controlled by a protein called mAChR4. Chronic alcohol use inhibits mAChR4, leading to liver damage.

3. Can the damage caused by alcohol be prevented?

Research suggests that protecting the gut early on can prevent liver damage. Drugs targeting mAChR4 could stop the harmful effects of alcohol.

4. Are there treatments for alcohol-related liver damage?

Most treatments focus on symptoms after damage. However, drugs that restore mAChR4 are being tested to prevent liver damage and treat alcohol addiction.

5. Why is protecting the gut important in preventing liver disease?

The gut plays a crucial role in liver health. If gut bacteria leak into the liver due to weakened defenses, it results in significant liver damage.

Disclaimer: This article, including health and fitness advice, only provides generic information. Don’t treat it as a substitute for qualified medical opinion. Always consult a specialist for a specific health diagnosis.