As our largest internal organ, the liver is little short of a powerhouse, performing more than 500 key functions in the body every day. It quietly goes about its responsibilities, filtering the blood of toxins, making bile so that we can digest meals, processing nutrients and regulating our metabolism.

The liver helps blood to clot, balances fluid levels, excretes cholesterol, hormones, drugs and bilirubin from the body and helps to keep the immune system on an even keel. I could go on but, to cut to the chase, if this organ isn’t functioning well then your health will eventually be affected. And poor liver function is not solely linked to heavy drinking. Your risk might be more significant than you think.

“When people think about liver disease, they think it relates to alcohol intake,” says Philip Newsome, professor of hepatology at King’s College London in King’s College Hospital and clinical adviser to the British Liver Trust (BLT). “Many people have no awareness that poor diets, a lack of exercise, being overweight and carrying too much fat around the middle means they likely have fat in and on their liver, which raises the risk of problems.”

According to the BLT, liver disease is the only major disease to see death rates continually rising, with figures having quadrupled in the past 50 years. Among the most common conditions is metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease, which is a chronic condition caused by a build-up of fat in the liver. It can affect people of all ages, although it is midlifers who are most likely to suffer.

“Significant liver damage doesn’t happen after one weekend of bingeing but takes place over many years of flogging the organ,” says Sarah Di Lorenzo, a clinical nutritionist based in Sydney who works with doctors and consultants to treat diet-related health issues. “But, as robust as it is, even our liver has a breaking point and the damage you may have caused in your twenties, thirties and forties may not become apparent until you are in your fifties or sixties.”

Left untreated, it can lead to liver cancer or failure in a small number of people, and if you have a lot of abdominal fat or type 2 diabetes, another risk factor for liver disease, you should ask your doctor for blood tests. But the good news is that the BLT says nine out of ten cases could be prevented if we tend to our liver’s health more carefully.

• Liver disease is a silent killer. Here’s how to reduce your risk

It was a spike in the number of middle-aged patients with early signs of liver damage referred to her clinic that inspired Di Lorenzo to write her new book, The Liver Repair Plan. In it she says there is much we can do to regenerate our liver and even reverse inflammation in people with MASLD.

Our liver is remarkably forgiving. “Its powers of self-repair are phenomenal,” Di Lorenzo says. “But its ability to regenerate diminishes with age so we really need to start caring for our liver as soon as we can.” Here’s what she recommends.

Cut down on alcohol

According to the BLT there is no such thing as a safe alcohol intake when it comes to liver health. The more you drink, the harder your liver has to work to process it. “Our liver has to use an enzyme called alcohol dehydrogenase (ADH) to convert the ethanol in alcohol and break it down into acetaldehyde,” Di Lorenzo says. “Another enzyme — aldehyde dehydrogenase (ALDH) — then breaks down the acetaldehyde into acetates, which are metabolised before leaving the body with carbon dioxide, so it’s a long and very taxing process.”

Both binge-drinking and moderate drinking can over time lead to liver inflammation and ultimately scarring or cirrhosis. “The risks get higher as you age because your liver breaks down substances slower than when you were younger, meaning alcohol toxins stay in the body longer,” Di Lorenzo says. “If you drink too much, cut down.”

Drink 3-4 cups of coffee each day

Drinking black coffee — even instant or decaf — could place you at a lower risk of liver disease, according to researchers at the universities of Southampton and Edinburgh, who tracked 384,818 coffee drinkers and 109,767 people who didn’t drink the black stuff.

Over 10.7 years, participants were monitored for any type of liver disease and showed that coffee-drinkers had a 21 per cent reduced risk of chronic liver disease and a 49 per cent reduced risk of early death from the condition. Their findings, published in BMC Public Health, revealed that drinking 3-4 cups of coffee a day offered the biggest benefits.

“Coffee is one of the best drinks for liver health as it helps to prevent the build-up of fat in the liver and increase antioxidants such as glutathione that protect against liver damage,” Di Lorenzo says. “It helps to lower the risk of cirrhosis, inflammation and liver disease in general, which is good news for coffee drinkers like myself.”

Lose weight

If you are carrying too much excess body fat, particularly around the middle, then losing it is a non-negotiable. “There’s a direct link between weight and fatty liver disease or MASLD,” Di Lorenzo says. “Overeating builds up fat on the body but also in the liver.”

Researchers from Boston University School of Medicine found that losing 7 to 10 per cent — 10-20lb (5-10kg) for someone weighing 14st (89kg) — of your body weight can reverse liver damage in some people who are overweight.

In his own studies, Professor Newsome has recently discovered that semaglutide-containing weight loss drugs such as Wegovy show promise in improving metabolic dysfunction-associated steatohepatitis (MASH), an advanced form of fatty liver disease where fat build-up has caused inflammation and scar tissue.

His findings, published in the New England Journal of Medicine, showed through biopsies taken after 72 weeks that 62.9 per cent of patients taking semaglutide had significant reductions in liver fat and inflammation, compared with 34.3 per cent of a placebo group.

Don’t bother with liver detox supplements

There’s a huge market for “liver detox” and “liver function” supplements containing ingredients such as milk thistle extract, artichoke extract, N-acetyl-L-cysteine (NAC), turmeric extract and choline. While it is tempting to think you can heal your liver by popping a daily pill, they are not worth the expense. The BLT advises against taking any supplements without first speaking to your GP and says many can do more harm than good.

Milk thistle is widely regarded as a liver cleanser but there is a lack of evidence to support its use and the BLT says it can cause side-effects that might be worse if you have underlying liver issues. “Anything that claims to detox your liver is a waste of money,” Di Lorenzo says. “The best way to detox your liver is to avoid processed foods, too much sugar and alcohol.”

Do take a vitamin D supplement

Professor Newsome says the one supplement we should be taking, at least from the end of September until April, is vitamin D. “I’d take an extremely cautious view of any supplements [for liver health] with the exception of vitamin D,” he says. A recent study of 3,905,594 people showed that those with low levels of the vitamin were at the highest risk of liver disease and scarring.

And in Nature Communications another group of researchers said that taking vitamin D supplements helped to reduce liver inflammation. “People with chronic liver disease usually have vitamin D deficiency,” Di Lorenzo says. “It’s absolutely essential for liver and general health.”

Increase your step count

Any form of physical activity is good for liver health. “If you can walk for 15 minutes 3-4 times a day, that is a good starting point,” Newsome says. A recent study of 91,000 people in the UK by researchers at the University of Oxford found that the more steps people take each day, the lower their risk of developing a fatty liver and MASLD. Every 1,000 steps higher (representing 10 minutes of walking) was associated with a 12 per cent lower risk of liver disease.

Taking a walk after a meal is even better. “Liver disease is driven by inflammation and inflammation can be increased by elevated blood glucose,” Di Lorenzo says. “Blood sugars spike after a meal and walking helps to offset that.” Even 2-3 minutes at a brisk pace is better for your liver than sitting down after a meal.

Don’t bother with DIY liver function tests

There are dozens of DIY liver function tests available to order online but the BLT does not recommend any home tests apart from the free NHS hepatitis C test. Other home tests cannot tell you if you have a liver condition or not and you should speak to your GP or a medical professional if concerned. You might be referred for a transient elastography (TE) test, also called a FibroScan. This tells you how stiff your liver is — a healthy liver is soft and supple — but won’t diagnose a liver condition on its own.

The BLT offers free FibroScans through its Love Your Liver roadshow (see website for details). If you want to have one privately you can do so at clinics. The Liver Clinic in London offers FibroScan liver scanning and personalised liver wellness consultations for £299 (theliverclinic.com).

The Liver Repair Plan by Sarah Di Lorenzo (Simon & Schuster Australia £18.99). To order a copy go to timesbookshop.co.uk. Free UK standard P&P on orders over £25. Special discount available for Times+ members. britishlivertrust.org.uk