What is Nonalcoholic Fatty Liver Disease?

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You may not have heard of it yet, but nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the United States and in other industrialized nations. The increase in prevalence and severity correlates with the rise in obesity and metabolic syndrome (a situation where someone has high blood pressure, high cholesterol, and Type 2 diabetes). Between 20% and 60% of adults with a body mass index (BMI) ? 30 have NAFLD.

What is NAFLD?

Just as the name implies, NAFLD is when fat builds up in the liver and alcohol abuse is not a factor. Insulin resistance is thought to play a key role by changing the way the body metabolizes fat so that fat is deposited in the liver. A fatty liver doesn’t function optimally and over time can lead to liver failure.

What are the Symptoms of NAFLD?

At the beginning there are often no symptoms, or non-specific symptoms such as fatigue, generally feeling blah and with low energy levels; or perhaps tenderness in the area of the liver (the upper abdomen on the right side of the body). As NAFLD progresses, it can include inflammation, fibrosis, the accumulation of proteins including collagen in the liver (this impairs liver function), and cirrhosis, which is when fibrosis leads to permanent scarring in the liver and irreversible damage. 

What are the Risk Factors for NAFLD?

Obesity, especially fat accumulating in the abdomen, is a primary risk factor for NAFLD. Other risk factors include insulin resistance and high levels of triglycerides, a type of fat found in the bloodstream that is associated with consuming too many calories, too much fat, too much sugar, or alcohol.

High levels of saturated fat and refined carbohydrates (such as sweetened beverages, cakes, cookies, candy, and snacks like chips) also increase risk of inflammation. High fructose corn syrup, which is often used as a sweetener in beverages and sweet snacks and desserts, is associated with increased rates of liver fibrosis.

Other conditions that may be associated with NAFLD include polycystic ovary syndrome, hypothyroidism, and obstructive sleep apnea. A history of cholecystectomy, independent of risk factors for gallstones, increases risk of NAFLD.

To learn about stopping NAFLD in its tracks or preventing it in the first place, don't miss the post Nonalcoholic Fatty Liver Disease: Prevention and Treatment.

By Lynn Grieger, RDN, CDCES, CPT, CHWC


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