Background

This post was prompted by a blog reader who was concerned about her 10-year-old son developing fatty liver. Unfortunately, this is becoming too common as you’ll soon learn.  During medical training I learned about fatty liver occurring in alcoholics.  Chronic intake of alcohol impairs the ability of a healthy liver to break down and release fat, leading to fat deposition inside the liver (more on this in a moment).

Fast forward to my practice today and although I don’t have a large percent of alcoholics in my Silicon Valley practice, I still see an alarming amount of Non-alcoholic Fatty Liver Disease (aka NAFLD), mostly secondary to the process of insulin resistance, a key focus of my work.  Like the name indicates, this form of fatty liver is being seen in individuals who have never even touched alcohol or drink very little.

In the US, up to 25% of individuals may have NAFLD.  In high risk regions like South Asia (India, Pakistan, etc.), the incidence can be as high as 30% in the general population and between 50-70% in type 2 diabetics.  Read this article for an in depth review of the NAFLD crisis in South Asia.  What’s especially of concern is that we are seeing NAFLD not only in adults, but also in children and teens.  We’ll discuss kids and teens towards the end of the post.

What Causes NAFLD (Non-alcoholic Fatty Liver Disease)?

As mentioned above, it’s insulin resistance that is the most common root cause for NAFLD and if you’re not familiar with the concept be sure to read this post and refer to my book.

Our body has limited storage space in our muscles and liver for carbohydrate storage (aka “glycogen”).  Glycogen storage capacity becomes even more limited if we are mostly inactive which has become a hallmark of modern day life.  When we exceed our liver’s capacity to store glucose as glycogen, the liver ends up having to flip a switch to convert glucose to fat.  The fancy word for this is “de novo lipogenesis” or DNL, which simply means making new fat out of carbohydrates.

Watch the 20 second video below from my brand new online wellness program which shows you DNL in action.

Notice how the red glucose car can’t find parking inside the liver because the liver is full of glycogen (watch the video again if this concept is not clear).  The glucose car’s only option is to enter a “fat machine” and get converted to fat (represented by the big yellow bus), which accumulates inside the liver, turning it into a fatty liver.

Keep in mind that the excess glucose stored need not come from sugar and sweets.  Many of my Indian and Asian patients have fatty livers fueled by excess rice, noodles, bread and even what they consider “healthy carbs” like quinoa, whole wheat bread, and whole grain cereals.

The word “fatty liver” becomes a misnomer since many of these patients are eating low-fat foods to fix their fatty liver (often recommended by their doctors, dietitians and/or internet resources), which instead contains more fat-producing carbohydrates.

By the way, if you have any doubt about the role of starches in producing fatty liver, just read about how the French delicacy foie gras is made.  Foie gras, which is duck or goose liver, is made from the unfortunately cruel process of force-feeding these birds with a combination sugar, starch and corn, to produce a fatty liver that’s then sold for human consumption.  There’s fat mixed into this bird feed as well, which is primarily to help with ingestion, but we can credit the rest of the ingredients for being the primary triggers for fat formation.  Many of us are turning our very own livers into foie gras with our modern lifestyle habits.

What Are Your Risks?

Insulin resistance is not just a major cause for NAFLD, it’s also the underlying mechanism for type 2 diabetes, heart disease and common cholesterol issues like high triglycerides and low HDL (healthy cholesterol).  If you have any of these conditions, there’s a very high likelihood you either have or are at high risk for developing fatty liver.  If you consume alcohol on top of this, then you are further multiplying your risk.  So let’s list off some of the typical risks. The more risk factors you have, the greater the chance you have fatty liver.

  • Excess weight, especially around the stomach. Also known as visceral fat which you can learn about in this post.
  • Abnormal blood glucose (prediabetes, diabetes)
  • Abnormal cholesterol, especially high triglycerides (blood fats) and/or low HDL (good cholesterol)
  • Metabolic syndrome: this is a condition that represents many of the above risks in combination.  Read about it here.
  • Ethnicity: South Asians, East Asians, Filipinos, Latinos, Pacific Islanders, etc. (these are also groups at high risk for insulin resistance/metabolic syndrome)
  • Lifestyle Risks: Diet high in processed foods (especially fructose and sugar), excess carbohydrates, sedentary behavior

How is NAFLD Diagnosed?

Regardless of what any specific test results show, if you have the risk factors we just discussed, you can already assume that you likely have some amount of excess fat in your liver.  You don’t want to wait for this problem to get worse and result in abnormal test results.

An expanding waistline and/or any signs of insulin resistance are reasons to already be proactive about preventing/reversing fatty liver, regardless of test results.

Now coming back to tests, if there is enough fat in your liver to cause inflammation, then you might see an elevation in the liver blood tests known as the ALT (alanine aminotransferase) and/or AST (aspartate aminotransferase).  In this case your doctor may order an imaging study like an ultrasound to document the presence of excess fat in the liver.  Some patients discover they have fatty liver after getting an imaging study of their abdomen for a different reason.  If you’ve ever had an imaging study like an ultrasound or CT scan of your abdomen for some other reason, I encourage you to read your official report to see if they mention “fatty liver.”  Often this may not be highlighted by your care team if they got the scan for a different reason.

Not everyone needs an imaging study to diagnose fatty liver.  Like I said, if you have insulin resistance, you likely have early stage fatty liver already.  If your blood tests are out of range, then I typically try lifestyle interventions to bring the inflammation down to normal.  In the early stages, fatty liver is quite reversible and blood tests can be normalized within a few months.  The decision to get an ultrasound depends on each individual case and you should discuss with your doctor.

Why is NAFLD and Your Liver Important?

I think the liver’s role in optimal health is too often overlooked, especially when it comes to diabetes and blood glucose control.  No matter how much we try to optimize insulin and prevent or reverse insulin resistance, if your liver is not working properly, then glucose control will not be optimal.  The liver is a primary organ for filtering toxins and any amount of excess fat in the liver will clog your filter.

Unless you live in an area of the world untouched by modern civilization, you are being exposed to multiple toxins daily through the food you eat, the air you breathe, the water you drink and even the endless products and cosmetics that come in contact with our skin.  In today’s world, we depend on a highly functioning liver filter more than ever.

A fat-clogged liver filter means your liver cannot effectively remove toxins, so they accumulate in your blood stream which causes more inflammation in the body.  A clogged liver also cannot properly metabolize glucose or lipids.  So this means you may have some combination of inflammation, elevated blood glucose and abnormal cholesterol.  In other words a set-up for diabetes, heart disease, cancer, autoimmune disease, neurodegenerative conditions like Alzheimer’s disease, and more.

Many of my female patients who struggle to lose weight despite diet and exercise often have a clogged liver filter leading to more toxins in their blood stream.  The way our body removes toxins is by creating more subcutaneous fat (externally visible fat) to store these toxins.  In other words, excess body fat formation is a protective mechanism to help our overworked liver in the job of removing toxins.  This effect is especially pronounced in women.  Eating clean, anti-inflammatory, nutrient dense foods and reducing toxin exposures as much as possible are key ways to restore normal liver function, in addition to reducing body fat.

Symptoms and Progression

NAFLD usually causes no symptoms until it has progressed to an advanced and likely irreversible stage.  That’s why it’s easy to ignore.  Your doctor diagnosed you 5 years ago with fatty liver and you are not changing your lifestyle habits because you feel fine.  Unfortunately many of the most dangerous conditions like high blood pressure, abnormal cholesterol and elevated blood sugar start off with no symptoms.  We call these “silent killers” for a reason and NAFLD can be added to the list.

If NAFLD progresses to the point of cirrhosis (liver failure), then symptoms such as yellowing of the skin (jaundice), fatigue, abdominal pain and unexpected weight loss may occur.  The longer you have fatty liver, the greater the chance of developing irreversible liver damage (aka cirrhosis) and liver cancer.  See the image below.  The percents are overall incidence, so 15-30% of healthy people go onto develop NAFLD.  As I mentioned earlier, if you already have the risk factors I listed, your risk is greater.  12-40% of NAFLD goes on to develop NASH (Non-alcoholic Steatohepatitis) which are specific inflammatory changes in the liver and this is typically when your liver tests like the AST and/or ALT become elevated.  15-25% of NASH goes onto cirrhosis and then the rest of the picture is bleak after that.

The excess fat in your liver is a toxin and the longer your liver is exposed to it the greater the chance of developing cirrhosis and cancer.  It’s no different than smoking.  The more you smoke and the longer you smoke, the greater your risk of lung cancer.  Excess fat in the liver, like cigarette smoke, is a toxic carcinogen that can cause cancer and/or liver failure.

Your child may not be smoking, but imagine if he or she has developed a fatty liver already which is becoming increasingly common.   The 10-year-old child I mentioned at the top of the post with a fatty liver will be exposed to an entire decade of toxic fat exposure by age 20 if he does not improve his lifestyle habits with the help of his family.  In fact, I’m fairly certain that other family members who probably eat a similar diet have some degree of fatty liver as well.  Now let’s talk in more detail about kids.

Kids, Teens and NAFLD

The stats on NAFLD in kids/teens are startling.  In the US, 17% of all 15-19 year olds and 38% of obese children have NAFLD.  Males are affected twice as often as females.  Read this short one-pager from the American Liver Foundation on NAFLD in kids.  Again, these are general US statistics.  If your child is from a high risk ethnic group like the ones I mentioned (Indian, Chinese, Filipino, etc.) and/or is showing any signs of being overweight or insulin resistant, then the risk becomes even higher.

Keep in mind that like adults, children from Asian backgrounds (South Asian, East Asian, etc.) require less excess weight to develop fatty liver. They may appear slender or be only slightly overweight, but if they come from a family with a strong history of diabetes and are not leading a healthy lifestyle, they may either already have fatty liver or be at very high risk.  The principles of my body fat post here can be applied to children.

Drinking sodas and sugar-sweetened beverages and consuming meals and snacks with additional sugar or even worse… fructose/high-fructose corn syrup sets them up for fatty livers at a young age.  

I’m writing this post during a hot summer day in a local coffee house and I’m seeing loads of children and teenagers walking in alone or with their families ordering giant frappuccino beverages, often with a muffin or pastry on the side.  All I can picture is their liver swelling up with fat like I show in the video.  A once in a while indulgence is ok, but unfortunately this is a regular habit for most.

Parents, aside from sugar-sweetened coffee beverages, think of what you’re giving your kids for meals and snacks.  The following are all potential fuel for a fatty liver:

  • Most breakfast cereals, especially those geared to kids.  Read the label and if there’s added sugar or fructose (can be labeled “corn syrup” or “high fructose corn syrup”), then avoid it.
  • Most other packaged breakfast foods like waffles
  • Packaged lunch meals and most packaged snacks
  • Excess servings of breads, rice, pasta and grains.   Typical day might be cereal for breakfast, flatbreads for lunch or snack, pasta or rice for dinner and then add on all the snacks and sugary beverages and you’ve got a set-up for fatty liver.  If your child or teen has been developing an expanding mid-section, that’s even more evidence for excess fat deposition directly into the liver.
  • Juice boxes

The teen years are when you need to be most aware of increased fatty liver risk.  As school work piles on and college admissions pressure rises, teens spend less time exercising and more time studying.  These study sessions often occur with friends in coffee houses, restaurants or other hangouts where junk foods are being consumed late into the night.  I’ve had several parents bring in their high school or college students to see me for their fatty liver or other signs of insulin resistance.

Treatment for NAFLD

The good news is that in my clinic we’ve had tremendous success in reversing fatty liver with lifestyle changes.  Some of the key changes include the following:

  • Completely eliminate artificial fructose sources from the diet such as high fructose corn syrup.  Avoid packaged foods, especially if fructose is on the label
  • Significantly limit sugar intake.  Generally no more than 4-6 teaspoons daily and read all packages for added sugar amounts.
  • Reduce excessive carbohydrate intake.  As mentioned, even healthier non-sweet carbohydrates in abundance can trigger fat storage in the liver
  • Avoid processed fats (like trans fats) and seed based oils (sunflower, corn, safflower, etc.) and consume healthier fats in moderation.  We’ve discussed healthy fats before, but think of a mixture of monounsaturated fats (extra virgin olive oil, avocados, avocado oil, etc.), omega-3 fats from cold water oily fish, leafy greens and flaxseed, and healthy saturated fats in moderation
  • Try episodes of fasting to give the liver time to remove excess fat and toxins.  Read my prior posts on fasting like the 5 myths here.
  • Avoid prolonged sitting (move after sitting for 20-30 minutes), increase walking steps, and add on exercise for a minimum of 30 minutes daily at least 3-4 days a week.
  • Limit or eliminate alcohol intake.  Different people have different sensitivities to alcohol.  If you have NAFLD, I think it’s best to avoid alcohol altogether.

Fatty liver is a potentially devastating condition that often affects the entire family.  You’re now armed with deep knowledge about the origins and the most effective ways to prevent and reverse fatty liver. Remember that even if you or your children have normal liver function tests, any signs of insulin resistance especially in combination with excess weight and the type of high risk diet I outlined, are enough reasons to take immediate action.

If you’ve been diagnosed with fatty liver, be sure to see your doctor regularly to help monitor this condition closely.  Do everything possible to reverse NAFLD or prevent it in the first place.