Nonalcoholic fatty liver disease (NAFLD) has now become the most prevalent liver disease in the world. In fact, it’s projected that within 20 years it will become the major cause of liver related morbidity and mortality, and a major cause of liver transplantation.
What is Nonalcoholic Fatty Liver Disease?
As the name implies, nonalcoholic fatty liver disease is when the liver becomes infiltrated with fat, mainly in the form of triglycerides and free fatty acids. This form of fatty liver is found in non-alcoholics.
To give you an understanding of what a fatty liver may look like, but not to gross you out, foie gras is technically fatty liver from a duck. Fortunately, the last time I ate foie gras was decades ago before I really understood what it was, otherwise I would have never ordered it off the menu. Yuck!
Types of Nonalcoholic Fatty Liver Disease
Nonalcoholic fatty liver disease is subdivided into two categories, non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH). NASH is slightly more advanced than NAFL because in addition to fatty liver there is damage or inflammation in the liver.
How many people have each type? According to John’s Hopkins University, it is estimated that 10-20% of Americans have NAFLD and 2-5% have NASH. Yet, according to Harvard University’s estimates 20-40% have NAFLD and 3-7% have NASH.
One reason for the variance is that most people who have nonalcoholic fatty liver disease don’t exhibit any symptoms, so people don’t always know they have it. Plus, the “gold standard” diagnostic test–a biopsy–isn’t practical or economical for most people to have done.
For the purposes of this article, I will be discussing both NAFL and NASH under the umbrella term of nonalcoholic fatty liver disease since the risk factors and treatment are similar.
Risk Factors for Nonalcoholic Fatty Liver Disease
As the number of people who have this disease continues to grow each and every year, we are learning more and more about possible risk factors and causes of nonalcoholic fatty liver disease.
Risk factors include:
- Insulin resistance
- Dyslipidemia (elevated triglycerides and LDL)
- Type II Diabetes
- Elevated blood pressure
- Sedentary lifestyle
- Some prescription drugs (tamoxifen, tetracycline)
Some people wonder what foods cause nonalcoholic fatty liver disease, and those include a diet high in sugar, saturated fat, and processed carbohydrates.
Another important fact is that the pediatric population isn’t immune to nonalcoholic fatty liver disease. In fact, some believe that the development of NAFLD begins in utero.
Nonalcoholic Fatty Liver Disease Symptoms
Fortunately—or unfortunately, depending on how you look at it—most people with nonalcoholic fatty liver disease are asymptomatic
If symptoms are present, they are quite nonspecific, such as:
- Discomfort in the upper right quadrant of your abdomen
This makes diagnosing the condition somewhat challenging, and this is partly responsible for the large discrepancy in how many Americans actually have this disease. Plus, it means that many cases go undiagnosed until it becomes far more advanced.
How Is It Diagnosed?
Diagnosing nonalcoholic fatty liver disease isn’t as cut and dried as we would like it to be. The gold standard is a liver biopsy particularly if you want to rule out NASH, but as I mentioned before this test can be impractical for many reasons. To make matters even more confusing, lean people can also develop nonalcoholic fatty liver disease, so anyone can develop it regardless of body size.
Most of the time we have to rely on the major risk factors like weight gain (or loss); a diet high in sugar, fats, and processed carbohydrates; and inactivity to drive suspicion for a NAFLD diagnosis.
You can also think about metabolic syndrome as being very closely tied to the development of nonalcoholic fatty liver disease, and you typically see some or all of the following with metabolic syndrome:
- Increased waist circumference
- Elevated blood sugar and insulin resistance
Sometimes, but not always, labs may show mild to moderately elevated liver enzymes (ALT, AST), elevated alkaline phosphatase, and/or elevated ferritin or transferrin saturation. On physical exam there may, or may not, be hepatomegaly which is enlargement of the liver.
The next step in making a diagnosis can include abdominal ultrasound, MRI, and CT scans to aid in the diagnosis.
Management of Nonalcoholic Fatty Liver Disease
I find that the following recommendations are the most effective for reversing fatty liver, which is certainly possible depending on how long someone has had it and other comorbidities, like diabetes for example, that make it more challenging to treat.
- Weight Loss: Despite the name “fatty liver,” you don’t need to treat nonalcoholic fatty liver disease with a low-fat diet—instead you want to eat a diet filled with healthy fats. I recommend eating a whole food diet (Modified Paleo, Mediterranean, low carb, etc.) and getting regular exercise. Even if you don’t lose any weight, exercise has been shown to reduce nonalcoholic fatty liver disease. Calorie restriction is another method to help with weight loss.
- Probiotics: Probiotics have been shown to help support leaky gut or intestinal permeability, lower total cholesterol, lower liver enzymes, reduce SIBO, and help with insulin resistance. A healthy gut is tied directly in with healthy liver health, so I always recommend a probiotic with patients who have fatty liver.
- Supportive Supplements: Including berberine (500 mg, 3 times daily), fish oil (2-4 g. daily), and milk thistle (250-500 mg daily).