Fatty liver disease is very common (20% of the adult population) and may cause abnormal liver function tests. It is the commonest reason for referral of a patient to a liver specialist so what do you need to know?

Causes: Fatty liver disease is caused by being overweight or obese, metabolic syndrome (mild type 2 diabetes, hyperlipidaemia, and hypertension), type 2 diabetes, too much booze (alcohol misuse), as well as few other rare conditions that should be excluded.

Implications: Roughly 15-20% of patients with fatty liver disease have steatohepatitis. This means that the fat in their liver is causing inflammation. Why this happens in some, but not others, is not known, it may be genetic. Regardless, if the fat in your liver is causing chronic inflammation it will lead to scarring or fibrosis. That is the laying down of scar tissue in your liver and this is bad for you. With chronic liver inflammation and fibrosis developing some patients develop cirrhosis, liver cancer or liver failure.

However, 80-85% of you with fatty liver probably have little inflammation in the liver in which case your liver disease is unlikely to progress, or will progress slowly.

How do I know whether or not I have inflammation and scarring of my liver? The reality is you cannot know unless you have a day case liver biopsy, which is straightforward procedure carried out by a radiologist under ultrasound guidance under local anaesthesia. You have to stay in hospital for about 6-8 hours in total from arrival.

Alternatives to liver biopsy: The alternative if a fibroscan, this is flick test of the liver. The machine simply flicks the side of your liver and determines how wobbly it is. A wobbly liver is healthy liver. The whole procedure takes less than ten minutes ad is painless. The downside is that a normal value does not exclude liver injury in the future, it just excludes significant liver fibrosis now at the time of testing.

What is the treatment of fatty liver disease? The only effective treatment for fatty liver disease for the vast majority of patients is exercise and a low carbohydrate diet. The low carbohydrate diet might be the Atkins diet or the Keto diet, but in essence the key is avoid heavy carbohydrate foods such as breads, pasta, rice, sweets and biscuits and sweet foods. You do NOT need to avoid fatty foods. Fats tend to need a lot of energy to burn them, whereas processed carbohydrates just get metabolised to fat in the liver. Some doctors advocate the use of Pioglitazone, but his drug also causes weight gain. My recommendation is diet and exercise. The importance of exercise sticks in my mind. Years ago I was shown the MRI of the liver of two Sumo wrestlers, one who was still wrestling and one who had retired. The sumo wrestler who had retired had lots more liver fat compared to the one still exercising and wrestling. The message being that exercise helps the body mobilise liver fat first!