Millions of Americans, and growing numbers of children, have fat silently growing in their livers. The condition, fatty liver, is largely an unfortunate side effect of the obesity epidemic. More than two-thirds of the American population is overweight or obese, according to Centers for Disease Control and Prevention researchers publishing in the "Journal of the American Medical Association." Fibrosis is a distinct stage in the progression of liver disease, which typically starts out as inflammation and can go as far as liver failure. Fibrosis is not something you will feel. Only a doctor can detect it, but if you have significant amounts of body fat or any of the risk factors for diabetes, talk to your doctor to check out your liver health.
Fatty Liver Prevalence
Up to 20 percent of Americans have fatty livers, according to the National Institute of Diabetes and Digestive and Kidney Diseases. The condition usually starts without any symptoms. As the fat continues to build up, blood tests can confirm whether you have nonalcoholic fatty liver disease, or NAFLD, which means about 5 to 10 percent of the weight of your liver comes from fat. When that fat starts to cause inflammation, growth of extra fibrous tissue and possibly some scarring, you may have nonalcoholic steatohepatitis, or NASH. These conditions are similar to the effects of alcohol on your liver, but they occur in people who drink little or no alcohol.
Fibrosis
Fatty liver diseases are progressive. Fibrosis is often the second stage of fatty liver conditions. A healthy liver acts as your body's chemical processor. It helps convert food into energy, stores vitamins, assists with digestion, fights germs and metabolizes the medicines you take. When fatty liver disease is beginning, you may first suffer liver inflammation. That means your liver enlarges and gets a little tender as it attempts to heal. You usually won't feel this start to happen. Viruses, infections and immune problems can also lead to fibrosis. Only certain medical procedures by your health care provider can detect fibrosis. Untreated liver inflammation leads to scarring. When excessive amounts of scar tissue start to replace healthy liver tissue, you have fibrosis.
Problems Associated With Fibrosis
Fibrosis represents an injury to your liver's cells. Scarred, fibrous tissue in your liver won't work the way a healthy liver should. The scar tissue keeps blood from flowing through your liver, and the unaffected part of the liver has to work harder as a result. Being insulin resistant or diabetic can increase the progression of fibrosis, Italian researchers publishing in the May 2008 "American Journal of Gastroenterology" find. Over time, fibrosis can progress to cirrhosis and liver failure.
Prevention and Treatment
You can prevent fatty liver, and consequently fibrosis, but no established medical treatment for fibrosis exists. The National Institutes of Health has prioritized research to find effective, well-tolerated medication to treat fatty liver, according to its "Action Plan for Liver Disease Research." As an example, its NASH clinical research network found somewhat promising results using a diabetes drug and vitamin E. The liver will attempt to heal itself. You can help by watching your diet, the NIH says. Reduce your weight and increase your level of physical activity. Reduce or eliminate alcohol and have your doctor counsel you on medications you take. Evidence also suggests that high-glycemic carbs, or those that quickly produce a spike in your blood sugar, cause an accumulation of fat in the liver. Harvard University researchers from Boston's Children's Hospital reported this assertion in the September 2007 "Obesity" journal. The mice in the study that ate high- and low-glycemic carbs weighed the same, but the mice that ate the "bad" carbs had twice the amount of body fat and liver fat as those that ate the "good" carbs.
References
- "Obesity"; Hepatic Steatosis and Increased Adiposity in Mice Consuming Rapidly vs. Slowly Absorbed Carbohydrate; Kelly B. Scribner, et al.; September 2007
- Siemens: What Is Liver Fibrosis?
- American Liver Foundation: The Progression of Liver Disease
- "Current Opinion in Gastroenterology"; Hepatic Fibrosis; Jingjing Jiao et al.; May 2009
- "The American Journal of Gastroenterology"; Association Between Liver Fibrosis and Insulin Sensitivity in Chronic Hepatitis C Patients; N. Taura, et al.; December 2006
- "JAMA" ; Prevalence and Trends in Obesity Among US Adults; Katherine M. Flegal, et al.; January 2010
