The liver is one of the hardest working organs in the human body. It detoxifies harmful substances, helps with digestion, stores nutrients, and regulates metabolism.
Author
- Dipa Kamdar
Senior Lecturer in Pharmacy Practice, Kingston University
Despite its remarkable resilience - and even its ability to regenerate - the liver is not indestructible. In fact, many everyday habits, often overlooked, can slowly cause damage that may eventually lead to serious conditions such as cirrhosis (permanent scarring of the liver) or liver failure.
One of the challenges with liver disease is that it can be a silent threat. In its early stages, it may cause only vague symptoms like constant fatigue or nausea.
As damage progresses, more obvious signs may emerge. One of the most recognisable is jaundice, where the skin and the whites of the eyes turn yellow. While most people associate liver disease with heavy drinking, alcohol isn't the only culprit. Here are five common habits that could be quietly harming your liver.
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1. Drinking too much alcohol
Alcohol is perhaps the most well-known cause of liver damage. When you drink, your liver works to break down the alcohol and clear it from your system. But too much alcohol overwhelms this process, causing toxic by products to build up and damage liver cells.
Alcohol-related liver disease progresses in stages . At first, fat begins to accumulate in the liver (fatty liver), often without any noticeable symptoms and reversible if drinking stops. Continued drinking can lead to alcoholic hepatitis , where inflammation and scar tissue begin to form as the liver attempts to heal itself.
Over time, this scarring can develop into cirrhosis, where extensive hardening of the liver seriously affects its ability to function. While cirrhosis is difficult to reverse, stopping drinking can help prevent further damage.
Even moderate drinking, if sustained over many years, can take its toll, particularly when combined with other risk factors like obesity or medication use. Experts recommend sticking to no more than 14 units of alcohol per week, and including alcohol-free days to give your liver time to recover.
2. Poor diet and unhealthy eating habits
You don't need to drink alcohol to develop liver problems. Fat can build up in the liver due to an unhealthy diet, leading to a condition now called metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD).
Excess fat in the liver can impair its function and, over time, cause inflammation, scarring, and eventually cirrhosis. People who are overweight - particularly those who carry excess weight around their abdomen - are more likely to develop MASLD. Other risk factors include high blood pressure, diabetes and high cholesterol.
Diet plays a huge role. Foods high in saturated fat, such as red meat, fried foods and processed snacks, can raise cholesterol levels and contribute to liver fat accumulation. Sugary foods and drinks are also a major risk factor. In 2018, a review found that people who consumed more sugar sweetened drinks had a 40% higher risk of developing fatty liver disease.
Ultra-processed foods such as fast food, ready meals and snacks packed with added sugar and unhealthy fats also contribute to liver strain. A large study found that people who ate more processed foods were significantly more likely to develop liver problems.
On the flip side, eating a balanced, wholefood diet can help prevent - and even reverse - fatty liver disease. Research suggests that diets rich in vegetables, fruit, whole grains, legumes, and fish may reduce liver fat and improve related risk factors such as high blood sugar and cholesterol.
Staying hydrated is also important. Aim for around eight glasses of water a day to support your liver's natural detoxification processes.
3. Overusing painkillers
Many people turn to over-the-counter painkillers such as paracetamol for headaches, muscle pain, or fever. While generally safe when used as directed, taking too much - even slightly exceeding the recommended dose - can be extremely dangerous for your liver.
The liver breaks down paracetamol, but in the process, produces a toxic by-product called NAPQI. Normally, the body neutralises NAPQI using a protective substance called glutathione . However, in an overdose, glutathione stores become depleted, allowing NAPQI to accumulate and attack liver cells. This can result in acute liver failure , which can be fatal.
Even small overdoses, or combining paracetamol with alcohol , can increase the risk of serious harm. Always stick to the recommended dose and speak to a doctor if you find yourself needing pain relief regularly.
4. Lack of exercise
A sedentary lifestyle is another major risk factor for liver disease. Physical inactivity contributes to weight gain, insulin resistance, and metabolic dysfunction - all of which can promote fat accumulation in the liver.
The good news is that exercise can benefit your liver even if you don't lose much weight. One study found that just eight weeks of resistance training reduced liver fat by 13% and improved blood sugar control. Aerobic exercise is also highly effective : regular brisk walking for 30 minutes, five times a week, has been shown to reduce liver fat and improve insulin sensitivity.
5. Smoking
Most people associate smoking with lung cancer or heart disease, but many don't realise the serious damage it can do to the liver.
Cigarette smoke contains thousands of toxic chemicals that increase the liver's workload as it tries to filter and break them down. Over time, this can lead to oxidative stress , where unstable molecules (free radicals) damage liver cells, restrict blood flow, and contribute to scarring (cirrhosis).
Smoking also significantly raises the risk of liver cancer. Harmful chemicals in tobacco smoke, including nitrosamines, vinyl chloride, tar, and 4-aminobiphenyl, are all known carcinogens . According to Cancer Research UK , smoking accounts for around 20% of liver cancer cases in the UK.
Love your liver
The liver is a remarkably robust organ - but it isn't invincible. You can protect it by drinking alcohol in moderation, quitting smoking, taking medications responsibly, eating a balanced diet, staying active and keeping hydrated.
If you notice any symptoms that may suggest liver trouble, such as ongoing fatigue, nausea, or jaundice, don't delay speaking to your doctor. The earlier liver problems are detected, the better the chance of successful treatment .
Dipa Kamdar does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
