Liver disease is frighteningly common worldwide.
Metabolic dysfunction-associated steatotic liver disease, or MASLD, is an umbrella term describing conditions related to a buildup of fat in the liver. Formerly known as nonalcoholic fatty liver disease, this condition affects 1 in 4 people worldwide. Among those with type 2 diabetes, insulin resistance, obesity or all three, the prevalence of MASLD increases to 3 in 4 people.
As a diabetologist, the possibility of liver disease is on my mind every time I see a patient. Understanding your risk of developing this common yet underrecognized condition is essential to treating it.
What is MASLD?
MASLD is a complex disorder with both environmental and genetic contributions. In its early stages, liver cells accumulate fat in a process called steatosis. Major sources of this fat include adipose tissue as well as fatty acids the liver makes in response to insulin resistance and excess caloric intake. This fat accumulation can enlarge the liver and interfere with its normal functioning.
Over time, fatty acids activate enzymes, which can produce toxic byproducts capable of causing liver cell injury, inflammation and scarring. This condition is better known as MASH, or metabolic dysfunction-associated steatohepatitis. Progression to MASH is more common in the presence of other risk factors such as type 2 diabetes, insulin resistance and metabolic syndrome.
Left unaddressed, MASLD and MASH can progress to liver scarring, failure and, in some cases, cancer. They also increase risk of death from cardiovascular disease and liver-related complications.
In the U.S., MASH is the leading cause of liver transplants due to hepatic cancer among women and in those 65 and older. It is also on track to overtake hepatitis B and C as the main reason people develop liver cancer and thus need a liver transplant.
Liver disease and type 2 diabetes
Three out of four people with type 2 diabetes have MASLD. Linking liver disease, type 2 diabetes and obesity is the key role insulin resistance plays in their genesis.
Obesity is associated with increased fat deposits around the internal organs and higher levels of fatty acids delivered to the liver. Accumulation of fat in the liver increases its resistance to insulin.
The large white spots in this image of MASLD indicate liver cells filled with excess fat droplets.
Dr. David Kleiner, National Cancer Institute/NIH via Flickr
Normally, insulin suppresses glucose production in the liver when blood sugar is high. When the liver becomes resistant to insulin, it produces more glucose despite elevated blood sugar levels, which in turn contributes to the development of type 2 diabetes.
A 2015 meta-analysis found that people with MASLD have a nearly twofold greater risk of developing type 2 diabetes than those without the disease. MASLD is also more likely to progress to MASH in the presence of type 2 diabetes.
MASLD…
