Thyroid Hormones Tied to Higher Risk of Fatty Liver

A meta-analysis of 36 studies with 198,254 people found clear thyroid differences in metabolic associated fatty liver disease (MAFLD). People with MAFLD had higher TSH and triiodothyronine (free and total) but lower thyroxine (free and total). Higher TSH may be an important risk factor, and the link changes with age.

Metabolic associated fatty liver disease (MAFLD) is one of the most common long-term liver problems. Doctors have wondered if the thyroid gland and its hormones play a role in who gets MAFLD.

Researchers looked at 36 studies with nearly 200,000 people. They pooled data from major medical databases to compare thyroid tests between people with MAFLD and those without.

One main finding was higher TSH in people with MAFLD. TSH is the hormone that tells the thyroid to work. Higher TSH may be a sign of increased risk for MAFLD.

The study also found hormone shifts: levels of triiodothyronine (T3), both free and total, were higher in MAFLD. Levels of thyroxine (T4), both free and total, were lower. These shifts show a different thyroid pattern in people with the liver disease.

Age mattered. The strength of the link between thyroid tests and MAFLD changed across age groups, so the pattern is not the same at every stage of life.

What this means for patients is that a simple blood test for TSH might add useful information when doctors assess fatty liver risk. Still, we do not know if changing thyroid levels will prevent or treat MAFLD. More studies are needed to find out whether thyroid care could help protect the liver.