A liver full of fat can be caused by anything that damages the liver. Doctors used to separate liver damage into that caused by alcohol and that not caused by alcohol (non-alcoholic fatty liver disease or NAFLD). Now we know that a liver damaged by excess alcohol has the same harmful consequences as a liver damaged by anything else, such as obesity or excess sugar intake (Gastroenterology, May 31, 2019).
The most common cause of liver damage used to be alcohol, but today it is far more likely to be caused by eating a lot of sugar-added foods or drinking anything with sugar in it. A fatty liver is common even in people who never drink alcohol. Up to 12 percent of people with a fatty liver keep on adding fat to eventually develop Non-Alcoholic Steato-Hepatitis (NASH), which is liver inflammation and permanent liver damage, called cirrhosis, that can cause liver cancer (Gastroenterology, August 23, 2018).
Excess Belly Fat Increases Heart Attack Risk, Even If You are Not Overweight
Another report shows that post-menopausal women who store fat primarily in their bellies are at increased risk for having heart attacks, even if they are not overweight (Eur Heart, June 30, 2019). Researchers followed 161,808 healthy women, aged 50–79 for 17.9 years and found that 291 developed heart disease during that period. Women with the highest percentage of belly fat had double the risk for heart disease, compared to those with the lowest belly fat. Furthermore, those with the lowest percentage of hip fat and highest percentage of belly fat (apple shape) had three times the risk for heart disease than those with lowest percentage of belly fat and highest percentage of hip fat (pear shape). The researchers concluded that reducing the amount of belly fat by itself would help to reduce heart attack risk significantly, even if the amount of hip fat was not reduced.
A Fatty Liver can Lead to Diabetes
People who store fat primarily in the belly are most likely to also store a large amount of fat in the liver. You can often diagnose diabetes just by looking at a person. People who have a big belly and small buttocks are at very high risk for being diabetic and suffering heart attacks (JAMA, 2017;317(6):626-634). To prevent your blood sugar level from rising too high after you eat, your pancreas releases insulin which is supposed to lower high blood sugar levels by driving sugar from the bloodstream into the liver. However, if your liver is full of fat, the excess fat prevents the liver from accepting the sugar and blood sugar levels can rise even higher (Eur J Gastroenterol Hepatol, Dec 2016;28(12):1443-1449). A high rise in blood sugar causes high blood insulin levels that convert blood sugar to a type of fat called triglycerides. Then insulin drives triglycerides into your liver. Having high triglycerides and a fat belly are signs of high blood insulin levels, and high blood levels of insulin constrict arteries to cause heart attacks. Insulin also acts on the brain to make you eat more, and on your liver to manufacture more fat, and on the fat cells in your belly to store that fat. See Fatty Liver Disease and Diabetes
Signs of a Fatty Liver