Life Extension Magazine®

Physician and patient talking about his risk of nonalchoholic fatty liver disease

Reverse Nonalcoholic Fatty Liver Damage

Nearly a quarter of U.S. adults have nonalcoholic fatty liver disease. A blend of probiotics and a prebiotic has been clinically shown to stop its progression and help reverse liver damage.

Scientifically reviewed by: Dr. Gary Gonzalez, MD, in August 2023. Written by: Richard Moore.

Most people have never heard of NAFLD.

Yet nearly one in four adults in the U.S. has nonalcoholic fatty liver disease (NAFLD).1-4

In the long term, NAFLD can cause fibrosis (scarring) of the liver, significantly impairing normal liver function.5-7

Advanced scarring, known as cirrhosis, is irreversible and can lead to liver failure.

The only treatment at that point is a liver transplant.8

Normal ways to address NAFLD include diet and lifestyle changes, and weight loss.

Innovative approaches include the medication metformin and certain nutrients.

Specific probiotics can now be added to this list.

In two clinical trials of people with NAFLD, a carefully designed blend of probiotics and a prebiotic decreased a marker of liver damage and reduced levels of fibrosis (scarring) from moderate or almost severe to normal.9,10

These findings suggest that the probiotic-prebiotic blend not only stopped the progression of the liver disease, but even reversed existing liver damage.

What Is Nonalcoholic Fatty Liver Disease?

Fat accumulation and inflammation in the liver can lead to chronic liver damage, scarring, and eventual liver failure.

In the past, alcohol abuse and viral hepatitis were the leading causes of chronic liver disease and death from liver cirrhosis.

NAFLD is now the number one chronic liver disease, and cause of liver cirrhosis deaths, in the United States.11,12

Back in the 1980s, experts first started to report on a newly recognized phenomenon: fat accumulating in the liver with no connection to alcohol intake or viral infection.13

The earlier phases of this condition are now referred to as nonalcoholic fatty liver disease (NAFLD), which accounts for about 75% of all chronic liver disease in the U.S.14 It affects roughly 25% of adults, both in the U.S. and across the world.4,11

When the disease becomes more severe, it is called nonalcoholic steatohepatitis (NASH). At this point, it can lead to liver cirrhosis, which is severe scarring of and damage to the liver.2

This damage to the liver is irreversible and can lead to complete liver failure.8

NAFLD Smolders Before Symptom Onset

NAFLD is common in obese adults, with around 50%-90% showing signs of fatty liver as the disease advances.15

But fatty liver disease can affect anyone with a metabolic disease such as metabolic syndrome or type II diabetes.16

In its early phases, NAFLD rarely causes specific signs or symptoms.17

Symptoms of early-stage NAFLD may include:17

  • Abdominal (belly) weight gain
  • Increase in cholesterol
  • Hypertension
  • Pain in the upper right abdomen
  • Persistent tiredness/fatigue
  • Binge eating

By the time major NAFLD symptoms manifest, significant scarring and hardening of the liver have already been inflicted. Symptoms of a more advanced disease may include:18

  • Abdominal swelling (ascites)
  • Swollen lower legs (edema)
  • Enlarged blood vessels beneath the skin’s surface
  • Enlarged spleen
  • Red palms
  • Yellowing of the skin and eyes (jaundice)

At advanced stages, NAFLD causes damage to the brain, vasculature, and other essential tissues.

An Interesting Finding

Researchers noted that fatty liver and liver damage are often seen in patients suffering from gastro-intestinal conditions, including inflammatory bowel and celiac disease.19,20

One thread that ties together metabolic disorders and nonalcoholic fatty liver disease is an unhealthy gut microbiota or microbiome.

The gut microbiota or gut flora is the population of different types of microorganisms—primarily bacteria—that naturally inhabit our gut.

A healthy, diverse microbiota is thought to promote health, but an unhealthy one is associated with the opposite.21,22

The Gut-Liver Connection

Here’s why the connection between gut health and liver health is so strong:

Most of the blood draining from the gastrointestinal tract (or gut) travels directly to the liver before entering general circulation.

This means that potentially harmful microorganisms, toxins, and other substances travel first to the liver after leaving the intestines.

An unhealthy mix of microorganisms in the gut also leads to inflammation in the intestines and what’s known as "leaky gut."23 That causes more and more microorganisms and toxic compounds to make their way directly to the liver.

What you need to know

New Hope for Fatty Liver Disease

  • Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver disease in Western countries. In its severe form, it can lead to liver failure and increase the risk of liver cancer.
  • There are generally no warning signs or symptoms of NAFLD until damage to the liver is already severe and irreversible. No drugs are currently approved to treat it.
  • Scientists have found that the population of microorganisms in the gut (the microbiota) have a dramatic impact on liver health.
  • In two clinical trials of patients with NAFLD, a mix of seven probiotic strains combined with a prebiotic reduced liver scarring and markers of ongoing liver damage. In other words, this blend stopped the progression of NAFLD and reversed existing liver damage.

The result of this toxic flow from the intestines causes oxidative stress and chronic inflammation, which contribute to nonalcoholic fatty liver disease and long-term liver damage.

Animal studies have shown that worsening of the gut microbiota can worsen fatty liver, while increasing beneficial bacteria can improve the health of the liver.24,25

As a result, improving the health of the microbiota and the gut with probiotics has become a major target of research into fighting fatty liver disease.

A Probiotic-Prebiotic Combination

Despite over four decades of research, there are still no medications approved by the U.S. Food and Drug Administration (FDA) to treat fatty liver disease.

Treatment is usually weight loss, through a combination of a healthy diet and exercise.

While weight loss is often crucial, scientists designed a blend of microorganisms they believed would favorably impact the liver, reducing risk and severity of nonalcoholic fatty liver disease (NAFLD).

In two clinical trials, a specific probiotic formulation has shown promising results for improving liver health.9,10

This formula is a blend of seven different probiotic strains:

  • Lactobacillus casei PXN® 37,
  • Lactobacillus rhamnosus PXN® 54,
  • Streptococcus thermophilus PXN® 66,
  • Bifidobacterium breve PXN® 25,
  • Lactobacillus acidophilus PXN® 35,
  • Bifidobacterium longum PXN® 30, and
  • Lactobacillus bulgaricus PXN® 39.

To provide maximum benefits, probiotics need to thrive and outcompete harmful bacteria.

For this reason, scientists combined these probiotics with fructooligosaccharide (FOS), a form of dietary fiber found in many plants. FOS serves as a prebiotic, a nutrient that "feeds" healthy bacteria.

With this extra energy source, the healthy bacteria are better equipped to survive and improve liver function and heal the liver.

Other Nutrients That Promote Liver Health

Some nutrients have also shown promise as a way to help control nonalcoholic fatty liver disease.

  • In human trials, vitamin E tocotrienols improved markers of liver health seen on an ultrasound, while reducing liver enzymes, C-reactive protein, and signs of oxidative stress.27-29
  • Phosphatidylcholine is an essential phospholipid which is a vital part of cellular membranes. Essential phospholipids have been used safely for years to protect liver function in patients with various liver diseases.30 In a number of human trials, phosphatidylcholine intake alone or with other nutrients improved NAFLD, reducing liver enzyme levels and improving ultrasound findings.30-32 A more bioavailable form of phospha-tidylcholine known as polyenyl-phosphatidyl-choline or PPC is the preferred choice for liver support as it specifically targets hepatocytes.
  • Extracts of the herb milk thistle, containing the compound silymarin, have long been used to protect liver function in patients with liver disease. Several clinical trials found that milk thistle, alone or in combination with vitamin E, and phosphatidylcholine reduces liver fat, fibrosis, and enzyme levels in patients with NAFLD.33-36
  • N-acetyl cysteine (NAC), a versatile sulfur-rich compound prevents liver damage following acetaminophen poisoning.37 NAC rapidly restores depleted glutathione levels, sparing liver cells from the effects of oxidative damage.38-40

Combating Fatty Liver: The First Study

Two human trials evaluated the use of this probiotic-prebiotic combination on subjects with a diagnosis of nonalcoholic fatty liver disease.

In the first, overweight and obese adults with NAFLD were randomized to receive the probiotic-prebiotic blend or a placebo for 28 weeks.9

At the study’s start, every subject had elevated liver enzyme levels in the blood, evidence of ongoing liver damage.

Over the course of the study, enzyme levels in the placebo group didn’t change. But those receiving the probiotic blend had multiple liver enzymes fall into the normal range.

In addition, all subjects at the start of the study had above normal levels of fibrosis in the liver, as identified by a specialized ultrasound technology specifically designed to assess liver fibrosis and fattiness. On average, this scarring was moderate to almost severe.

The group receiving the probiotic-prebiotic blend dropped their fibrosis scores all the way into the normal range. The placebo group had no significant change by the end of the study.

These findings suggest that the probiotic-prebiotic blend stopped the progression of liver disease and reversed liver damage that was already present.

Combating Fatty Liver: The Second Study

The second study had a similar design, but enrolled adults with NAFLD who were not overweight or obese.10

The findings echoed those from the first study. Evidence of ongoing liver damage was reduced significantly in those receiving the probiotic-prebiotic blend, and fibrosis scores dropped into the normal range.26

In a further benefit, in both studies the group taking the probiotic-prebiotic blend had a substantial decline in C-reactive protein blood levels. C-reactive protein is a marker of systemic inflammation, indicating that overall inflammation was reduced.

This probiotic-prebiotic blend offers a way to lessen or even reverse the damage done by nonalcoholic fatty liver disease.


Nonalcoholic fatty liver disease affects roughly a fourth of the adult population in the U.S.

This progressive liver condition can lead to liver cirrhosis and liver failure, requiring a transplant. It is also a major contributor to the development of liver cancer.

Research has found a link between the microbiome and liver health.

Two clinical studies confirm that a specially formulated blend of seven probiotics and a prebiotic can help stop the progression of NAFLD and reverse the damage already done.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.


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