Excess dietary salt alters liver metabolism and drives progressive fatty liver disease in lean individuals through distinct inflammatory pathways, according to a pre-clinical study published September 28, 2026, in Molecular Metabolism by researchers at Duke-NUS Medical School.
How High-Salt Diets Trigger Lean MASH
Fatty liver disease is typically linked to obesity, but a growing number of people with normal body mass index figures develop severe disease manifestations. Researchers at Duke-NUS Medical School, alongside teams from the National Heart Centre Singapore, Duke University School of Medicine, and University College London, engineered a diet-induced mouse model to investigate this phenomenon. The findings show that a high-salt diet alters liver metabolism by increasing fat breakdown while simultaneously activating immune cells that spark severe liver inflammation and scarring, known as metabolic dysfunction-associated steatohepatitis (MASH).
“While obesity-associated MASH is closely linked to excess fat accumulation, our model shows that high dietary salt can alter liver metabolism and activate inflammatory pathways even without obesity,” said Dr. Zhou Jin, lead author of the study and principal research scientist at the Duke-NUS Cardiovascular & Metabolic Disorders Signature Research Programme. Up to 40 percent of populations in Singapore and other westernised Asian regions experience MASH, including an increasing proportion of lean patients facing elevated risks of liver failure, cirrhosis, and liver cell cancer.
Biological Differences Between Lean and Obese Liver Disease
The newly developed laboratory model mirrors the core features of lean MASH: relatively low levels of accumulated liver fat paired with intense inflammation and tissue scarring. This cellular profile matches clinical observations in human patients who present with minimal liver fat yet suffer from severe disease progression. According to the research team, treatments designed to address obesity-driven liver damage fail to target the distinct biological drivers operating in patients with normal body weight.
“This study challenges the assumption that fatty liver disease follows the same biological pathway in every patient,” said Professor Lok Shee-Mei, vice-dean of the Office of Research at Duke-NUS. The preclinical model provides researchers with a tool to investigate why conventional therapies fall short in non-obese cohorts. Professor Derek John Hausenloy of the Duke-NUS Cardiovascular & Metabolic Disorders programme noted that the model allows investigators to analyze the condition as a whole-body disease. Because cardiovascular complications remain a primary cause of mortality in MASH patients, the team aims to test whether salt-induced injury mechanisms extend beyond the liver to affect heart health.
Next Steps in Biomarker Discovery and Treatment
Investigators plan to utilize the new diet-induced mouse model to locate early diagnostic biomarkers for lean MASH. Researchers will also test specific compounds designed to selectively block the salt-induced inflammatory pathways identified in the Molecular Metabolism report. Funding for the research was provided by the Singapore Ministry of Health through the National Medical Research Council Office, MOH Holdings Pte Ltd, and the National Research Foundation, Singapore.
Frequently Asked Questions About Lean MASH and Salt Intake
What is lean MASH?
Lean MASH is a severe, progressive form of metabolic dysfunction-associated steatohepatitis that develops in individuals with a normal body mass index, characterized by liver inflammation and scarring despite low fat accumulation.
How does dietary salt affect the liver in lean individuals?
According to the Duke-NUS study, excess dietary salt alters liver metabolism by increasing fat breakdown while activating immune cells that trigger inflammation and tissue damage without requiring obesity.
Has this salt-induced mechanism been verified in humans?
The causal role of high salt intake on lean MASH currently derives from a pre-clinical mouse model and requires further verification through clinical studies involving human patients.
What organizations supported this liver disease research?
The study received financial backing from the Singapore Ministry of Health via the National Medical Research Council Office, MOH Holdings Pte Ltd, and the National Research Foundation, Singapore.
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