Why the Name Change Matters
In June 2023, a multinational consensus of hepatology societies officially replaced the term non-alcoholic fatty liver disease (NAFLD) with metabolic dysfunction-associated steatotic liver disease (MASLD). Simultaneously, non-alcoholic steatohepatitis (NASH) became metabolic dysfunction-associated steatohepatitis (MASH). This was not a trivial relabelling exercise. The change reflects fundamental shifts in how we understand, diagnose, and approach this increasingly prevalent condition.
What Was Wrong With the Old Names
Defined by What It Is Not
NAFLD was defined negatively — fatty liver that is "not alcoholic." This is problematic for several reasons. It defined a disease by exclusion rather than by its actual cause. It required clinicians to rule out alcohol as a cause before making the diagnosis, which was often impractical and inconsistently applied. And it implied that the condition was simply the absence of alcoholism rather than a distinct metabolic disease with its own pathophysiology.
Stigma Associated With "Fatty" and "Alcoholic"
The term "fatty liver" carries significant stigma, implying that the condition is the patient's fault due to overeating. The word "alcoholic" in the name — even prefixed by "non" — created confusion and discomfort. Patients reported embarrassment about their diagnosis and reluctance to discuss it, which hindered treatment adherence and open communication with healthcare providers. Research showed that these naming conventions actively discouraged people from seeking care.
Excluded Patients Who Also Drink
The old framework created a false dichotomy: you either had alcoholic liver disease or non-alcoholic fatty liver disease. In reality, many patients with metabolic liver disease also consume moderate amounts of alcohol. The binary classification forced clinicians to assign one label or the other, when in fact both metabolic and alcohol-related factors can coexist and interact.
What the New Names Mean
MASLD: A Positive Diagnosis
MASLD is defined by the presence of hepatic steatosis (liver fat) plus at least one cardiometabolic risk factor:
- BMI above 25 (or above 23 in Asian populations) or waist circumference above sex-specific thresholds
- Fasting glucose above 5.6 mmol/L or type 2 diabetes
- Blood pressure above 130/85 mmHg or antihypertensive medication
- Triglycerides above 1.7 mmol/L or lipid-lowering medication
- HDL cholesterol below sex-specific thresholds or lipid-lowering medication
This is a positive, inclusive diagnosis based on what the disease actually is: a metabolic condition affecting the liver.
MetALD: The New Middle Ground
For patients who have metabolic liver disease and consume alcohol at levels between moderate and heavy, a new category was created: MetALD (metabolic and alcohol-related liver disease). This acknowledges the reality that metabolic and alcohol-related factors frequently coexist.
Why This Matters for Your Health
Earlier Identification
The new criteria are broader and more inclusive, meaning that more people with early-stage metabolic liver disease will be identified. Under the NAFLD framework, patients who did not fit neatly into the "non-alcoholic" category were often left without a diagnosis or appropriate monitoring.
Reduced Stigma Improves Outcomes
When patients are not embarrassed by their diagnosis, they are more likely to engage with treatment, discuss their condition with family members, and seek follow-up care. The removal of stigmatising language is expected to improve adherence to lifestyle interventions and screening protocols.
Gut Health Implications
The shift to metabolic framing aligns with the growing understanding that MASLD is driven by systemic metabolic dysfunction, of which gut health is a central component. The gut-liver axis — through which bacterial endotoxins, microbial metabolites, and bile acids directly influence hepatic fat metabolism — is now recognised as a key pathway in MASLD pathophysiology. This reframing opens the door to gut-targeted interventions as part of standard MASLD management.
What You Should Do
- If you were previously diagnosed with NAFLD or NASH, your diagnosis is now MASLD or MASH — the condition itself has not changed, only the terminology
- Ask your doctor about screening if you have any of the cardiometabolic risk factors listed above
- Recognise that MASLD is a systemic metabolic condition, not just a liver problem, and that gut health plays a foundational role
- Consider a comprehensive gut assessment through GutIQ to identify whether digestive dysfunction may be contributing to metabolic stress on your liver
The renaming from NAFLD to MASLD is more than semantics. It represents a shift toward understanding liver disease as part of a broader metabolic and gut-mediated picture — and that shift opens up more effective approaches to prevention and treatment.