NASH vs. NAFLD: Understanding the Differences
Published by Dr. Venn-Watson
Dr. Eric Venn-Watson’s Highlights
Fatty liver disease affects one in three adults in the United States and is the leading cause of liver transplants.
There are two types of fatty liver disease, and one causes significant, irreversible liver damage.
Taking a supplement like fatty15 can help protect liver health by guarding liver cells against oxidative damage and supporting liver function.
Liver disease was once thought of as a condition that developed solely due to the misuse of alcohol. Today, liver disease is extremely common and affects more people who do not misuse alcohol.
Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are two liver diseases that affect people who rarely drink or who do not use alcohol at all. If you’re concerned for your liver health, you should understand the differences between these two conditions and what can cause them.
We’ll help you unpack both conditions, giving you an overview of each, and tell you what you can do to help support your liver health. First, let’s talk about why liver health matters.
Why Is the Liver So Important?
The liver is a large organ that performs over 500 vital functions in your body. A few of the most important include:
- Producing bile, which removes waste from the body
- Filtering out toxins and balancing chemical levels in the blood
- Removal of bilirubin, a byproduct of red blood cells
- Production of cholesterol and proteins and regulation of amino acids
- Conversion of glucose to glycogen and back to glucose, which helps regulate blood sugar levels
You can’t live without your liver, and it takes care of itself well. The liver can even regenerate after some types of damage, but some damage is irreversible, including damage from fatty liver disease.
What Is Fatty Liver Disease?
The liver can store fat, but it’s not designed to store it. When excess fat is stored in the liver, it affects your liver function. Eventually, it can lead to liver scarring, cirrhosis, and even liver cancer.
If you have fat stored in your liver, you have fatty liver disease. Fatty liver disease can be broken down into two categories: NAFLD and NASH.
The first “stage” of fatty liver disease is called nonalcoholic fatty liver disease. This disease causes fat to be stored on the liver, but the fat stored on the liver has not yet caused any liver tissue scarring or damage.
Of the one in three Americans who have fatty liver disease, about 10 to 20 percent have NAFLD. It’s often referred to as “the silent liver disease” because it’s very rare to experience symptoms. Your doctor may diagnose NAFLD by using blood tests, imaging, and/or liver biopsy.
Who’s at Risk for NAFLD?
Unlike alcoholic fatty liver disease, which is directly related to alcohol misuse, NAFLD occurs in people who rarely consume or never consume alcohol. Researchers aren’t entirely sure why some people develop fatty livers and some don’t, but there are some risk factors associated with fatty liver disease.
You’re more likely to develop NAFLD if you:
- Suffer from obesity. People with a BMI over 30 are at higher risk for developing NAFLD
- Have high blood triglyceride levels
- Have insulin resistance or have type 2 diabetes
- Have high cholesterol
- Have a family history of fatty liver disease
- Having metabolic syndrome
However, just having one or some of these symptoms doesn’t mean you will get fatty liver disease. Inversely, if you don’t have these symptoms, it’s still possible for you to develop fatty liver disease, but it’s very rare.
If you have NAFLD and make no lifestyle changes to help manage your condition, you could develop nonalcoholic steatohepatitis or NASH. About two to five percent of adults living with NAFLD will develop NASH.
NASH is a progressive form of NAFLD. With NASH, the liver is damaged beyond repair. It begins to develop scar tissue, a condition known as fibrosis. Fibrosis can lead to cirrhosis of the liver, which is a severe form of liver damage that is not repairable and can be life-threatening, leading to liver failure.
If you have NASH, you still may not have any symptoms. If you do, symptoms can include:
- Weakness and fatigue
- Pain in the upper right side of the abdomen
- Yellowing of the skin and eyes (called jaundice)
- Unexplained rapid weight loss
- Visible, spider-like blood vessels on the skin
If you have these symptoms, it’s important to see your healthcare provider and have your liver enzymes checked immediately. Your doctor may then order additional imaging, including a FibroScan, which can detect changes in the liver and measure scarring.
After these tests, your doctor will likely order a liver biopsy, which will help them determine whether you have liver scarring and how far your disease has progressed.
Who’s at Risk for NASH?
If you have a nonalcoholic fatty liver (NAFL), you are at risk of developing NASH. Most people who have chronic liver disease (like NAFLD) don’t have to develop NASH.
Lifestyle changes and dietary adjustments can significantly reduce your risk of developing NASH and can help you manage your fatty liver disease.
How To Keep Your Liver Healthy
Maintaining a healthy liver is important; taking a few simple steps can pay dividends in your liver’s livelihood. If you don’t consume alcohol, the CDC recommends you do not start.
If you do, make sure your alcohol use is limited. While alcoholic steatohepatitis is a different condition from NAFLD and NASH, it harms the liver in the same way.
In addition to monitoring your alcohol use, make sure you are managing other known health conditions, too. If you have high blood pressure or type 2 diabetes, for instance, it’s important that your doctor closely monitors your conditions to ensure they do not progress.
Maintain a Healthy Weight
One of the biggest risk factors for developing NAFLD and NASH is being overweight. You’re considered overweight if you have a BMI of 25+. If you need to trim down a healthier body weight, speak to your healthcare provider about the best weight loss methods.
People who are most successful with weight loss usually focus their attention on getting in more movement and consuming fewer calories.
Eat a Healthy Diet
There’s a direct link between our diets and NAFLD. High fructose corn syrup (especially in drinks) is associated with NAFLD. You can avoid this ingredient by removing soda and sweetened beverages from your diet and avoiding foods that are prepackaged and sweetened with it.
Instead, focus on whole grains, lean proteins, fruits, vegetables, and the right types of fat. Fat gets tricky because there is a lot of misinformation about what fats are, how they work, and whether they are “good” or “bad.” Let’s take a closer look.
Explaining Fatty Acids
The history of how fats got such a bad reputation starts in the late 1970s. Dietary guidelines were issued advising Americans to avoid all fats. We were dying of cardiovascular disease; it was the number one killer.
Fast forward an entire generation, and we’ve definitely seen some changes. Most middle-aged adults grew up in households that opted for skim milk over whole and substituted low-fat food options for full-fat versions.
Our health (especially our heart health) should be safe now, right? Wrong. The dietary guidelines missed the mark.
While we avoided fat, manufacturers added other ingredients to our food to replace the fat, like sugar. Our health actually declined. The occurrences of type 2 diabetes in children skyrocketed, and fatty liver disease became common. What’s more, heart disease is still the number one killer of adults.
What We Learned
Not all fats are bad. Some fats are healthful, and some are even essential. Essential means we need them to thrive, but our bodies can’t readily make them on their own. Omega fatty acids are some of the best-known essential fatty acids, although there is a newly discovered essential fatty acid that science supports has 3 times the benefits of omega-3s
Which essential fatty acid, you ask? Pentadecanoic acid, or C15:0 for short.
What Is C15:0?
C15:0 is an odd-chain saturated, essential fatty acid that strengthens our cells and helps us live healthier, longer lives. It protects our bodies and our livers at their core: by improving the health of our cells.
How It Works
C15:0 repairs cells and reverses cellular aging by restoring cellular strength and revitalizing cellular energy.
C15:0 reverses cellular aging by:
- Strengthening cellular membranes. Cell membranes break down as we age. This happens in all cells, including the ones in your liver. C15:0 is a sturdy fatty acid that integrates into cell membranes and fortifies them, protecting them from oxidative stress. In studies, C15:0 improves cellular strength by 80%.
- Clearing damaged cells. Cells in our bodies sometimes lose their functionality, but they don’t die. Instead, they hang around in our bodies, creating inflammation. C15:0 activates AMPK, which helps to clear out these damaged cells. Activation of AMPK also helps restore total body homeostasis, helping regulate liver function, glucose uptake, and immunity.
- Regulating inflammatory response. C15:0 significantly calms and lowers proinflammatory cytokines, a key driver of aging and an underlying condition of multiple age-related diseases.
- Rescuing our mitochondria. Mitochondrial function declines with age. C15:0 helps restore mitochondrial energy output (ATP) and helps reduce reactive oxygen species by 45%. In one peer-reviewed study, C15:0 was shown to increase ATP levels in cells by 350%.
- Activating PPARɑ and PPARẟ receptors. These special receptors support functions like metabolism, immunity, heart, and liver function. In relevant models, C15:0 activates these receptors and helps recalibrate these functions, bringing them back into balance.
By increasing your C15:0 intake, you can support your whole body and liver health in one fell swoop.
Great, I’ll Take Some C15:0: Where Can I Find It?
Glad you asked. C15:0 is found primarily in whole dairy products, like whole milk and full-fat butter.
However, increasing your intake of these foods poses a two-part problem: First, it means consuming additional calories you might not need, and second, while C15:0 is present in whole-fat dairy products in trace levels, there are much higher levels of “bad” even-chain saturated fatty acids that continue to be associated with poorer health.
What’s the Solution?
We created one. Fatty15 is the once-a-day, sustainable version of C15:0 that contains just one ingredient (pure, vegan-friendly C15:0) and lets you skip the cows and the calories.
By taking just one fatty15 per day, you can restore your circulating levels of C15:0 and help support your liver function and your total body wellness. Further, fatty15 was created to be bioavailable and easy to absorb.
In contrast, C15:0 in milk and other foods is attached to branches of lipids called triacylglycerides, aka triglycerides. That means our gut has to use digestive enzymes to break down these triacylglycerides to release C15:0 as a free fatty acid.
Once C15:0 is released, it is ready to be absorbed. These multiple steps can make our absorption of C15:0 from foods less efficient. In contrast, FA15 in fatty15 is our proprietary pure, powder C15:0 ingredient already in free fatty acid form and ready to absorb.
Less work for the gut, more good C15:0 for our bodies. More promise of good health and a happy liver.
The Only Fatty You’ll Want
Your liver health is important, and you can support it even if you already have a diagnosis of fatty liver disease.
Maintaining a healthy weight, eating a balanced diet, managing your current medical conditions, and taking a liver-supportive supplement like fatty15 can put you on the fast track to liver wellness.
Eric Venn-Watson M.D.
Senior Scientist, Co-Founder
Eric is a physician, U.S. Navy veteran, and Co-founder and COO of Seraphina Therapeutics. Eric served over 25 years as a Navy and Marine Corps physician, working with the special forces community to improve their health and fitness. Seraphina Therapeutics is a health and wellness company dedicated to advancing global health through the discovery of essential fatty acids and micronutrient therapeutics.
You May Also Like...
What Is a Blue Zone? Where the Healthiest People Live
How long will you live? If you’re like most people, you don’t give that question much thought until you have reason to truly consider your own longevity.
Maybe you’ve received a medical diagnosis that could shorten your lifespan....
Cellular Theories of Aging: Modern Aging Theories
Every year, we get another year older, and at a certain age, we begin to wonder just how many years we have left. Just how long, barring unexpected events, can we expect to live and live healthfully?