Break the “Silence” Between Obesity and Fatty Liver Disease

Fatty liver disease has become one of the most common health concerns linked to obesity. For many people, this condition develops quietly without symptoms in the early stages, earning it the reputation of being a “silent” disease with loud consequences.

On a global scale, nonalcoholic fatty liver disease (NAFLD) – recently re-termed metabolic dysfunction-associated steatotic liver disease (MASLD) – affects roughly 32% of adults worldwide, with rates almost twice as high in men as in women. The prevalence has been steadily increasing, nearly doubling since 2005, with the highest rates observed in the Americas and Southeast Asia. If current trends go unchecked, the health consequences will be staggering by 2030.¹

The numbers are even more striking when looking at specific populations. In people with type 2 diabetes, MASLD occurs in up to 75% of patients, and among those with severe obesity, prevalence can reach 90%. Experts warn that, without intervention, MASLD is on track to become the leading reason for liver transplantation by the end of this decade.²

Fatty Liver 101: Names, Stages, and Causes

To clear up any confusion, we need to make sure we’re on the same page with the current terminology.

In 2023, experts updated the medical terminology for fatty liver disease. What was once known as nonalcoholic fatty liver disease (NAFLD) is now called metabolic dysfunction–associated steatotic liver disease (MASLD). Why? The old name focused only on what the disease was not (alcohol-related) rather than what it is: metabolic dysfunction due to excess body weight, insulin resistance, type 2 diabetes, high cholesterol, and/or high blood pressure.

Its more advanced stage, previously called nonalcoholic steatohepatitis (NASH), is now referred to as metabolic dysfunction–associated steatohepatitis (MASH). The word steatohepatitis means “fatty inflammation of the liver,” marking an inflammatory stage of the disease process where liver damage progresses and complications increase.

Initially, fat begins to accumulate inside liver cells, and for many people, the liver can quietly tolerate this fat buildup without major issues. In this pre-inflammation stage of MASLD, the fat often just continues to accumulate. The liver continues to function, which is why most people may not experience symptoms at this stage. Occasionally, there may be subtle signs, such as fatigue or mild abdominal discomfort, but these are often easily overlooked by many people. The danger is that, while the liver seems to be coping, the stage is set for inflammation and more serious damage later on.

In about 10-20% of cases, the situation escalates: fat overload begins to irritate and inflame the liver, leading to MASH. Once inflammation sets in, the liver attempts to heal itself by forming scar tissue, known as fibrosis. If scarring worsens, it can eventually reshape the entire organ into cirrhosis, where healthy liver tissue is replaced by stiff, damaged tissue. In some cases, this process of increasing inflammation and tissue remodeling can lead to liver cancer (hepatocellular carcinoma).²

Unfortunately, the story does not end there. The liver acts as a warning signal that the whole body might be out of balance. Fatty liver is not simply fat sitting in the liver; it’s a dynamic, whole-body process where diet, metabolism, gut health, and inflammation all collide. Hence, MASLD is both a liver disease and a broader metabolic warning sign.²

A fatty liver develops over time due to a web of interconnected factors²:

• Metabolism and excessive diet: Overeating, particularly diets high in sugar and unhealthy fats, overloads the liver with energy it can’t process, leading to fat buildup.
• Gut-liver connection: An unhealthy gut microbiome (the balance of bacteria in the intestines) can leak harmful byproducts into the bloodstream, which travel straight to the liver and spark inflammation.
• Immune response and inflammation: Once liver cells are damaged, the body’s immune system reacts, creating a cycle of inflammation and scarring.
• Systemic impact: Because these mechanisms affect not just the liver but also blood vessels, kidneys, and other organs, MASLD often shows up alongside cardiovascular disease, type 2 diabetes, and other chronic health conditions.

Risk Factors and Consequences

Certain risk factors increase the likelihood of fatty liver disease. People struggling with obesity and excess weight (especially abdominal fat), high triglycerides or LDL cholesterol, type 2 diabetes, and high blood pressure are at higher risk. When several of these factors occur together, they form metabolic syndrome, a cluster of conditions that often coincides with fatty liver.

Fat can accumulate in the liver for years without causing harm. But over time, the drag on the body’s systems stymies other metabolic processes. Insulin resistance, for example, promotes further fat accumulation in the liver, while excess liver fat worsens insulin resistance. This creates a vicious cycle: as each factor feeds the other, inflammation and metabolic dysfunction escalate. This back-and-forth relationship helps explain why MASLD is so common in people with type 2 diabetes and other features of metabolic syndrome.²

Fatty liver disease also affects the heart and blood vessels. Cardiovascular disease (CVD) is a leading cause of death in MASLD patients, with the risk rising as liver disease severity increases. Studies show that people with MASLD are more likely to develop left ventricular dysfunction, atherosclerotic heart disease, and ischemic heart disease. Researchers believe that the link between heart disease and liver disease comes from a combination of metabolic dysfunction, chronic low-grade inflammation, gut microbiome changes, and altered processing of metabolic byproducts.²

Understanding these risk factors and their consequences helps highlight the importance of early detection and management.

Is Fatty Liver “Curable?”

In many cases, MASLD/NAFLD can be reversed or significantly improved, primarily through lifestyle changes. Losing weight, improving your diet, controlling blood sugar and cholesterol levels, and avoiding alcohol can all help reduce liver fat and even reverse the condition in its early stages.²

To do this, lifestyle changes are key2:

• Weight loss: Losing 7-10% of body weight is often recommended, with greater weight loss associated with more substantial improvements in liver fat, inflammation, and even fibrosis.
• Dietary adjustments: Limiting fructose, particularly from sweetened beverages and processed foods, can help reduce liver fat accumulation.
• Exercise: Engaging in at least 150 minutes per week of moderate physical activity, including both aerobic and resistance training, helps reduce liver fat and supports overall well-being.
• Managing underlying conditions: Controlling diabetes, high blood pressure, and high cholesterol supports liver health, and avoiding alcohol is crucial, especially in the inflammatory stage (MASH).

In more advanced cases of MASH, lifestyle changes alone may not fully reverse liver fat or scarring. However, controlling underlying conditions and adhering to recommended lifestyle modifications can still slow or stop disease progression.²

Researchers are also finding increasing evidence of the gut-liver connection: the gut microbiome, in an unhealthy and unbalanced state, actively influences the development of fatty liver. Changes in gut bacteria, increased intestinal permeability (sometimes referred to as “leaky gut”), and bacteria-derived metabolites can travel through the bloodstream to the liver, triggering inflammation and disrupting normal metabolic processes. While probiotics have shown promise in reestablishing gut flora, more research is needed before they can be recommended as a standard treatment for fatty liver disease.²

For patients with severe obesity, and particularly those with overlapping metabolic complications, bariatric surgery can address several problems at once. By reducing excess weight, the surgery alleviates the liver’s workload, improves insulin sensitivity, lowers inflammation, and helps the body’s metabolism function more efficiently.

In patients with early-stage MASLD, weight loss surgery can prevent fat buildup from progressing to inflammation, essentially stopping the disease before it escalates. In those with MASH, surgery may allow the liver to heal itself, resolving inflammation and even reversing some existing scarring (fibrosis). Clinical studies show that these improvements in liver tissue can last for years, making surgery a valuable option for certain candidates.²
MASLD can be a long-term condition, but it’s not necessarily permanent as long as the appropriate steps are taken.

Check In On Your Liver

Fatty liver is often discovered during routine blood tests, particularly if you have risk factors like obesity or type 2 diabetes, and abnormal results may prompt further evaluation. Standard diagnostic tools include blood tests, imaging, and sometimes a liver biopsy.

At Higa Bariatrics, patients now have access to the FibroScan, a non-invasive device that measures liver stiffness. Understanding liver stiffness and verifying healthy liver function is especially important before bariatric surgery, as it helps clinicians assess the level of risk associated with MASLD/MASH, as well as the surgery itself.

Take the first step toward protecting your liver and improving your overall health – schedule a consultation at Higa Bariatrics to check your liver health with FibroScan and explore personalized bariatric solutions.

1. Teng, M. L., Ng, C. H., Huang, D. Q., Chan, K. E., Tan, D. J., Lim, W. H., Yang, J. D., Tan, E., & Muthiah, M. D. (2023). Global incidence and prevalence of nonalcoholic fatty liver disease. Clinical and molecular hepatology, 29(Suppl), S32–S42. https://doi.org/10.3350/cmh.2022.0365.
2. Grander, C., Grabherr, F., & Tilg, H. (2023). Non-alcoholic fatty liver disease: pathophysiological concepts and treatment options. Cardiovascular research, 119(9), 1787–1798. https://doi.org/10.1093/cvr/cvad095.