Introduction of new terminology for fatty liver diseases

Posted on: 24th June 2023

A group of multinational liver societies and leading doctors have announced new terminology for liver diseases related to fat accumulation in the liver. The new names are for the diseases that have previously been called ‘fatty liver disease’; non-alcohol related fatty liver disease (NAFLD) and NASH.

They propose that

  • Steatotic liver disease or SLD will now be used to encompass various causes of fat accumulation in the liver
  • Metabolic dysfunction-associated steatotic liver disease (MASLD) will replace non-alcohol related fatty liver disease (NAFLD).
  • NASH the more serious form of NAFLD will now be called Metabolic-associated steatohepatitis (MASH)
  • Met-ALD – this is a new name that has been created for people who have MASLD but who also drink alcohol
  • Cryptogenic SLD – this is the name doctors will use for fatty liver disease where the cause is unknown as people do not have any of the metabolic risk factors.

The decision to change the terminology was made through a collaborative process involving global liver societies, patient advocacy organisations, regulatory experts, and industry representatives. However, the British Liver Trust has not been involved in the process. The goal was to create clearer and more comprehensive names that could improve research, funding, and patient outcomes.

The change in terminology is deemed necessary due to various reasons, including the lack of adequate nomenclature (set of rules used to name things)  since the original description of the condition. Though the term ‘NAFLD’ was introduced in 1986, the exponential rise in NAFLD publications was most notable from 2000 onwards. However, with advancements in research, it has become apparent that most diseases classified as NAFLD are related to metabolic factors such as obesity, insulin resistance, and high cholesterol or lipids.  One reason that the group has recommended the change is also to reduce stigma by taking out the word 'fatty' and removing the word ‘alcohol’. It's also important to have a name that tells us about the causes of the condition. In liver disease it is important to understand the cause as treating this can help the liver recover.

The British Liver Trust is concerned that these new terms are very medical and might confuse patients in the short term. It may also take a long time for these new names to be adopted and for the public to understand them. For now, we will continue to use the existing terminology (alongside the new terms where appropriate) so that we can continue to raise awareness about this serious type of liver disease. If you are worried or concerned or are not sure what this means in relation to your own condition please speak to your doctor or call our helpline 0800 652 7330.

For further information about the change in terminology, visit: Global NAFLD Nomenclature Consensus Development | AASLD