Non-alcoholic fatty liver disease (NAFLD), a condition of extra fat buildup in the liver, is on the rise — it now affects roughly 20% to 40% of the US population. It usually doesn't cause any symptoms and is often first detected by accident when an imaging study (such as an abdominal ultrasound, CT scan, or MRI) is requested for another reason. A fatty liver may also be identified on an imaging test as a part of investigating abnormal liver blood tests. NAFLD is intimately related to conditions like diabetes and obesity. It's also linked to an increased risk of cardiovascular disease. Understanding NAFLD and its causes, consequences, and treatment options is still a work in progress.
The many faces of fatty liver disease
There are lots of medical terms related to fatty liver disease, and it can get confusing. The main medical umbrella term NAFLD refers to a fatty liver that is not related to alcohol use. NAFLD is further divided into two groups:
- Non-alcoholic fatty liver (NAFL), otherwise known as simple fatty liver, or
- Non-alcoholic steatohepatitis (NASH)
Why the type of fatty liver disease matters
Distinguishing between simple fatty liver and NASH is important. Why? Because for most people, having simple fatty liver doesn't cause sickness related to the liver, whereas those with NASH have inflammation and injury to their liver cells. This increases the risk of progression to more serious conditions like fibrosis (scarring) of the liver, cirrhosis, and liver cancer. NASH cirrhosis is expected to be the number one reason for liver transplant within the next year. Luckily, most people with NAFLD have simple fatty liver and not NASH; it is estimated that 3% to 7% of the US population has NASH.
It takes a liver biopsy to know if a person has simple fatty liver or NASH. But the possible (though infrequent) complications and cost of a liver biopsy make this impractical to do for everyone with NAFLD.
Scientists are trying to find noninvasive ways to identify who is at the greatest risk for fibrosis, and thus who should go on to have a liver biopsy. Possible approaches include biomarkers and scoring systems based on blood tests (such as the NAFLD fibrosis score and Fibrosis-4 index), as well as elastography (a technology which uses soundwaves to estimate fibrosis based on the stiffness of the liver).
Keeping your liver healthy
If you have been diagnosed with fatty liver disease, it is important to keep your liver as healthy as possible and avoid anything that can damage your liver. Here are some important things you should do.
- Don't drink too much alcohol. How much is too much remains controversial, but it's probably best to avoid alcohol completely.
- Make sure that none of your medications, herbs, and supplements are toxic to the liver; you can crosscheck your list with this LiverTox Even acetaminophen (the generic ingredient in Tylenol and some cold medicines) may be harmful if you take too much for too long, especially if you have liver disease or drink alcohol heavily.
- Get vaccinated to protect against liver viruses hepatitis A and B.
- Control other health conditions that might also affect your liver, and check with your doctor if you might have other underlying, treatable diseases contributing to your fatty liver.
- Get regular screening tests for liver cancer if you already have cirrhosis.
What about drug therapy?
Unfortunately, there are no FDA-approved medications for fatty liver disease. So far, the two best drug options affirmed by the American Association for the Study of Liver Diseases for biopsy-proven NASH are vitamin E (an antioxidant) and pioglitazone (used to treat diabetes). However, not everyone will benefit from these treatments, and there has been some concern about safety and side effects. If you have NASH, it's best to speak to your doctor about whether these treatments are appropriate for you, as they are not for everyone. There are more drugs in the pipeline, some with promising initial study results.
The most effective fatty liver treatment: lifestyle changes
The good news is that the most effective treatment so far for fatty liver disease does not involve medications, but rather lifestyle changes. The bad news is that these are typically hard to achieve and maintain for many people. Here's what we know helps:
- Lose weight. Weight loss of roughly 5% of your body weight might be enough to improve abnormal liver tests and decrease the fat in the liver. Losing between 7% and 10% of body weight seems to decrease the amount of inflammation and injury to liver cells, and it may even reverse some of the damage of fibrosis. Target a gradual weight loss of 1 to 2 pounds per week, as very rapid weight loss may worsen inflammation and fibrosis. You may want to explore the option of weight loss surgery with your doctor, if you aren't making any headway with weight loss and your health is suffering.
- It appears that aerobic exercisealso leads to decreased fat in the liver, and with vigorous intensity, possibly also decreased inflammation independent of weight loss.
- Eat well. Some studies suggest that the Mediterranean diet may also decrease the fat in the liver. This nutrition plan emphasizes fruits, vegetables, whole grains, legumes, nuts, replacing butter with olive or canola oil, limiting red meat, and eating more fish and lean poultry.
- Drink coffee, maybe? Some studies showed that patients with NAFLD who drank coffee (about two cups every day) had a decreased risk in fibrosis. However, take into consideration the downsides of regular caffeine intake.
Even though it can be difficult to make these lifestyle changes and lose the weight, the benefit is immense if you have fatty liver, so give it your best effort! And remember, the greatest risk for people with a fatty liver is still cardiovascular disease. Not only can some of these lifestyle changes improve or resolve your fatty liver, they will also help keep your heart healthy.
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