The liver is a very important vital organ, the second largest after the skin, which provides the most important functions in regulating homeostasis in the human body. It has a number of functions such as detoxification and removal of waste products, drugs and other harmful substances, storage of certain vitamins, minerals and sugar, production of bile and essential plasma proteins, and also creates immune factors that help fight infections as well as many other functions.
Non-alcoholic fatty liver disease (NAFLD) is defined as excessive accumulation of fat in the liver in the absence of secondary causes of fatty liver, such as significant alcohol consumption, viral hepatitis, or drugs that can cause fatty liver. The term NAFLD encompasses a continuum of liver abnormalities, from non-alcoholic fatty liver disease (NAFLDs, simple steatosis) to non-alcoholic steatohepatitis (NASH).
This disease begins with fatty accumulation in the liver (hepatic steatosis). The liver can remain fatty without hepatic impairment (NAFDL), but with different mechanisms and possible disorders, it can progress to non-alcoholic steatohepatitis (NASH), a condition in which steatosis combines with inflammation and sometimes fibrosis. NAFLD, in turn, can lead to complications such as cirrhosis and hepatocellular carcinoma.
NAFLDs are the most common liver disorder worldwide and are present in approximately 25% of the world’s population. It is more common in developed countries, and over 90% of obese, 60% of diabetics and up to 20% of people of normal weight can develop this disease. NASH is the leading cause of chronic liver disease and the second most common cause of liver transplantation in the United States and Europe.
Obesity and type 2 diabetes mellitus are important risk factors for NAFLD. Other risks include being overweight, metabolic syndrome (defined as at least three of the following five medical conditions: obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum HDL cholesterol), a diet high in fructose, and older age.
