Top Causes of Elevated Liver Enzymes + How to Treat High AST and ALT
Elevated liver enzymes may act as a warning that something is damaging your liver and should never be ignored.
Learn what causes elevated liver enzymes, what symptoms you may present with and more importantly how to treat this problem...
Liver Enzyme Made Easy (AST & ALT)
What are liver enzymes and what do they mean?
In the most simple sense liver enzymes is used to represent a series of test that can help to determine if your liver is functioning appropriately.
The standard "liver function tests" include:
- Alanine Transaminase (or ALT for short): ALT is produced in the liver cells known as hepatocytes and is a very specific marker of liver cell damage.
- Aspartate Transaminase (or AST for short): AST is not quite as specific as ALT for liver damage as it is also found in skeletal muscle, heart muscle, and kidney tissue. AST tends to rise with ALT if liver damage is present.
- Alkaline Phosphatase (or ALP for short): ALT is produced by the cells lining the bile ducts or the "plumbing" of the liver. A rise in ALT is commonly seen in conditions that caused blocked "ducts" such as bile stones or direct damage to the bile ducts.
- Gamma-glutamyl transferase (or GGT for short): GGT is found in liver, kidney, pancreatic and intestinal tissues. If GGT is elevated along with ALP this is highly indicative of an obstruction in the plumbing of the liver or may indicate gallbladder disease.
If you are dealing with "elevated liver enzymes" you most likely have an issue with AST and ALT.
While ALP and GGT are still important to assess what is happening in the liver most physicians refer to AST and ALT as the "liver enzymes".
So what do liver enzymes tell us?
Liver enzymes help us determine if there is damage to the cells of the liver or direct damage to the liver tissue itself.
If damage is present in the liver then it will react by releasing these special enzymes (AST and ALT) into the bloodstream as the cells become "leaky".
So if you are dealing with an elevation in liver enzymes that is an indication that there is some sort of damage occurring in your liver.
And this is obviously less than ideal.
Your liver is considered a vital organ (meaning you can't live without it) and it helps to detoxify chemicals you come into contact with, break down supplements/medications, red blood cell production, hormone production and plays a critical role in protein synthesis and biochemical reactions.
These reactions are critical to everyday life which is why you can't live without your liver.
In addition, we have no way to create "synthetic" livers in the event that you have permanently damaged your liver.
So it's in your best interest to keep yours healthy.
For the purposes of this article, we want to focus on the most common causes of elevated liver enzymes so that you can determine what is causing the problem and then prevent long-term and permanent damage.
When we talk about an "elevation" in AST and ALT we really need to define what we are talking about, what kind of numbers you should be worried about and how to address them.
The "Rise" in Liver Enzymes
There are two basic types of elevated liver enzymes:
The first is a slight or subtle increase in AST and ALT which and the second is a massive increase in AST and ALT.
We are going to focus on the slight or subtle increase in AST and ALT (levels less than 100-300 times normal) because this usually indicates a chronic condition that results in low-grade inflammation and damage to the liver over time.
Massively elevated AST and ALT (levels greater than 10x the normal reference range) usually indicates an acute life-threatening condition such as liver failure from medication overdose, physical trauma to the liver or massive organ failure.
While massive elevations in liver enzymes are obviously important, the subtle increase is more relevant to most people because they can do something about it.
So what does it mean to have elevated liver enzymes?
Most laboratory reference ranges include a "range" of values to indicate that you are "normal".
If you go outside (or too high) this range then you are considered to have elevated liver enzymes.
The standard range largely depends on the laboratory but in general, is somewhere around 0-45 IU/l for ALT and 0-30 IU/l for AST.
If your AST and ALT are higher than the 45 and 35 then they are said to be "elevated".
And this is a big issue because by definition that means that you are experiencing some sort of liver damage.
More important than just knowing that your liver function tests are elevated is figuring out why they are elevated, to begin with, and the picture behind their elevation.
We will discuss the most common causes of elevated AST and ALT below (including treatment) but first, let's talk a little bit about lab values.
While the laboratory data shows there is a "range" for both AST and ALT you can picture the damage done to your liver on a spectrum.
On this spectrum, the higher your AST and ALT values are the more damage that exists in the liver.
This correlation exists to the point that you can almost define disease states based on the elevation of AST and ALT.
Patients with chronic hepatitis tend to have AST and ALT levels in the 30-120 range, those with autoimmune hepatitis tend to have levels in the 100-600 range.
Perhaps more important than these two causes is liver damage caused by a condition known as non-alcoholic fatty liver disease.
If your liver enzymes are elevated then there is a VERY high chance the damage to your liver is actually caused by your diet and a condition known as insulin resistance.
The elevation in AST and ALT observed in this condition tends to be mild (and may even be missed!).
People with non-alcoholic fatty liver disease will often have a very "modest" elevation in AST and ALT, somewhere in the 30-70 range for both.
What's more interesting is that people with this condition tend to be completely asymptomatic, which means that this condition is really only picked up on routine screening.
Patients with this condition often tend to also be overweight and have issues with glucose regulation.
Once it is identified that you do indeed have elevated liver enzymes your Doctor should begin to do a workup to figure out the cause.
Once the cause is determined then you can focus on the treatment.
When thinking about what causes damage to the liver it's important to focus on those conditions which are VERY common as opposed to rare conditions.
Most Common Causes of High AST/ALT
There are MANY, MANY conditions and disease states that lead to high AST and ALT but the majority of them can be boiled down to just a few conditions.
This list below is not all encompassing but should give you a good idea on how to get started.
Emphasis should be put on #1 and #2 which will most likely account for the vast majority of slight elevations in AST and ALT in most people.
The reason you should focus on these is that they are treatable and reversible.
#1. Non-Alcoholic Fatty Liver Disease (AST and ALT levels in the 30-70 range)
This is by far the #1 cause of elevated AST and ALT in the United States with a prevalence of up to 30% (1) and it's primarily caused by insulin resistance and almost entirely preventable!
How it happens:
As you consume sugary, especially refined sugar, your body rapidly metabolizes glucose into fats or lipids in the liver through a process known as de novo lipogenesis.
As the influx of glucose becomes more than your body is able to handle this fat begins to get stored in the liver.
As fat increases in the liver, it results in damage to the liver cells.
This damage is seen in the serum (bloodstream) as an elevation in serum levels of AST and ALT.
If the diet is not changed or if insulin resistance is not managed then this fat accumulation will eventually cause permanent and chronic damage to the liver.
This may result in complete liver failure over time.
It's very important to find out if your elevated liver enzymes are caused by non-alcoholic fatty liver disease because it can be treated and damage can be prevented.
Those with AST and ALT caused by fatty liver disease can be diagnosed by checking AST/ALT levels in conjunction with fasting glucose, Hgb A1c, serum cholesterol and by checking the BMI.
People who have metabolic syndrome and high AST/ALT should be evaluated for diabetes and insulin resistance.
Treating NAFLD and High AST/ALT
If you have liver damage from insulin resistance and obesity then you should be aggressive with your treatment.
The following therapies have been shown to reduce (and even reverse) liver damage from NAFLD:
- Weight Loss: Losing weight has been shown to reduce AST and ALT levels and reverse liver damage. There's a right way to lose weight and a wrong way, so focus on improving your diet and exercising more as opposed to simply restricting your calories.
- Medications: Certain medications such as metformin, GLP-1 agonists, SGLT-2 inhibitors and carb blockers have been shown to reverse insulin resistance help with weight loss and improve LFT's.
- Dietary Intervention: Insulin resistance is often caused by over-consumption of refined sugars and carbohydrates. You can impact insulin levels by reducing the amount of sugar and refined carbohydrates you consume (2)(bread, pasta, bagels, pizza, sugary drinks, etc.).
- Supplements: Certain supplements have been shown to reduce inflammation and oxidative stress which is critical in the pathogenesis of NASH and NAFLD. These supplements have been shown in studies (3) to help: Vitamin E, Vitamin C, Berberine, Probiotics, Glutathione precursors (Betaine).
- Exercise: Exercise helps to increase insulin sensitivity and may assist with weight loss. If you have elevated liver function tests and you are overweight make sure you don't forget the basics like exercise.
Treatment should then be focused on managing blood sugar, dietary changes, and specific medications/supplements.
#2. Alcoholic Liver disease (AST and ALT in the 70-700 range)
Alcoholic liver disease used to be the #1 cause of liver failure in the United States until it was taken out by non-alcoholic fatty liver disease and obesity.
Having said that it is still an important cause of liver damage in many people.
The liver damage caused by alcohol consumption occurs after prolonged and excessive drinking (usually years worth of damage to the liver).
It can occur from daily drinking or episodes of binge drinking.
Consuming 30 grams of undiluted alcohol for 10 years (4) may result in a condition known as cirrhosis (permanent liver damage).
The mechanism of damage is similar to that of non-alcoholic fatty liver disease.
Overconsumption of alcohol results in direct damage to liver cells and puts an increase in demand on your body.
You can think of alcohol as a liquid carbohydrate source that must be metabolized by the liver.
This produces chronic damage and fat accumulation in the liver much like non-alcoholic fatty liver disease.
What's interesting is that alcohol consumption, even in small amounts, can make existing liver conditions (such as non-alcoholic fatty liver disease) even worse.
Because of this, it is recommended that you stop consuming alcohol if you have elevated liver enzymes - even if it is not primarily caused by alcohol consumption.
The primary treatment for alcoholic liver damage is to stop consuming alcohol, in some cases, this is enough to completely reverse the condition or at least stop further damage.
#3. Prescription Medications (Low-grade elevation of AST/ALT)
Certain prescription medications can also cause liver damage.
Medications must be metabolized by the body and that metabolism usually occurs in the liver.
As your body breaks down certain medications it creates byproducts that can still remain active and some may even be toxic.
If these metabolites are left in the body they can cause local injury to the liver or injury to other tissues.
The perfect example is Tylenol (5).
In small doses, your liver can metabolize it without issues, but once doses become excessive Tylenol metabolites can cause serious damage to your body and even result in acute liver failure.
In the case of Tylenol, even daily doses of 5 to 8 grams per day may lead to liver damage over time.
This is very important to consider because Tylenol is available over the counter and commonly used for aches and pains.
Other medications that may cause liver damage include:
If you are taking a medication that is causing liver damage (and it isn't necessary to take) then the treatment is to discontinue or reduce the dosage of medication.
#4. Certain Supplements (Low-grade elevation of AST/ALT)
Even some supplements have been shown to cause acute liver damage and cause a rise in liver function tests.
The supplements that tend to cause issues are hard to pinpoint exactly.
Most of the information we have stems from case studies of patients who were taking very suspect types of "fat burners" and combining them with many different weight loss supplements.
Some case studies (10) show that these type of supplements can cause acute liver damage in certain susceptible individuals.
This shouldn't be enough to cause alarm among most people, however.
The people who experience these side effects tend to do so when they use poor quality supplements that likely contain actual hormones and medications in them.
Not all supplements are regulated in the same way that the pharmaceutical industry is, which means that you can get more (or less) than what you are expecting.
Some weight loss supplements have even been shown to contain toxic doses of actual thyroid hormone (11).
You can avoid all of these potentially dangerous side effects simply by purchasing high-quality supplements that ship from the United States (don't purchase supplements overseas) from reputable companies and suppliers.
Also, please avoid supplements with "too good to be true" advertising, especially in the weight loss area.
Using these types of non-gimmicky supplements can actually help with weight loss - provided they are used correctly.
#5. Autoimmune Hepatitis (AST/ALT in the 100 to 600 range)
While autoimmune hepatitis is not as common as the other 4 listed above it's still worth mentioning.
Autoimmune disease is on the rise in the United States and is, therefore, a very important cause of diseases.
The term autoimmune means exactly as it sounds - auto attack by the immune system on your body or tissues.
In autoimmune hepatitis (12), your immune system creates antibodies that circulate in the body and target your liver as the "enemy".
This results in inflammation and chronic damage which can lead to irreversible damage in some cases.
Who is at risk for developing this condition?
It turns out, like most autoimmune diseases, that women get this disease much more frequently than men.
What causes it?
While the exact mechanism and trigger are unknown it is felt that the etiology of autoimmune hepatitis is multifactorial.
What this means is that the disease can be "triggered" or "turned on" by certain environmental factors such as exposure to toxins or infection.
Autoimmune diseases tend to occur in individuals with a genetic predisposition, meaning not everyone is at risk.
#6. Viral Hepatitis & Other Viral Diseases (AST and ALT depend on the degree of the damage)
An elevation in liver function tests will prompt an immediate workup for basic viral hepatitis by your physician.
A history of intravenous drug use, old tattoos or high-risk behavior may increase the risk that your liver damage is caused by a viral infection.
Hepatitis B and Hepatitis C, both of which are viral infections, may lead to chronic and long-term damage to the liver.
Hepatitis A (13) (spread via the fecal-oral route) on the other hand tends to be more acute in nature with an acute spike in AST and ALT in a short period.
This should be compared to chronic Hepatitis B and C (14) which tend to cause a slower and more long-term elevation in liver function tests.
But these aren't the only viruses that cause liver damage.
CMV and EBV (15) (both of which are very common) may also cause an acute spike in liver enzymes.
The damage from CMV and EBV tends to be short-lived however and shouldn't cause long-term damage.
In addition, the rise in liver enzymes is almost always associated with other systemic symptoms such as fatigue, malaise, sore throat (in the case of EBV) and fever.
It's worth mentioning viral infections because they are an important cause of liver damage, but they are generally caught and treated appropriately in most patients.
#7. Copper and Iron Overload Syndromes (AST and ALT depend on the degree of the damage)
Another sinister cause of liver damage and thus elevated liver enzymes is an overload of certain metals in the body.
Overload syndromes such as Iron overload (also known as hemochromatosis (16)) and copper overload (also known as Wilson's disease (17)) result in deposition of high levels of metals in specific tissues which results in damage to these tissues over time.
While iron and copper deposit in more than just the liver, they definitely can and do cause liver damage if they are deposited there.
The prevalence of Hemochromatosis is estimated to be around 1 in every 200 to 500 people which are fairly high.
Generally, those people who have Hemochromatosis are often asymptomatic and the diagnosis is made by finding a slight elevation in liver function tests with abnormal serum iron levels.
As long as it is caught early the damage can be mitigated.
Wilson's disease is much less common and more difficult to diagnose but still worth mentioning as it is an overload disease that can cause liver damage.
Tips to Naturally Treat and Improve Liver Function
Regardless of the cause of liver damage in your body, there are several steps that you can take to improve liver function and perhaps impact your liver enzyme levels.
If you aren't sure where to start then you can consider following these guidelines.
The #1 cause of elevated liver enzymes in the United States is non-alcoholic fatty liver disease which is caused by obesity and insulin resistance.
It's also one of the most treatable causes of liver damage.
Find the Root Cause
Whenever possible your main goal should be to find the source and cause of your elevated liver enzymes.
Once you know the source you can direct your treatment to that specific problem.
The root cause of non-alcoholic fatty liver disease = insulin resistance and obesity (which should be your target treatment).
The root cause of alcoholic fatty liver disease = alcohol intake.
The root cause of iron overload syndrome = inability to get rid of iron adequate (treatment should focus on reducing oral iron intake and phlebotomy (18)).
You should never "ignore" elevated liver enzymes because they indicate something wrong in your body!
I also recommend keeping an eye on your AST and ALT levels with a goal to try and get both to less than 20 IU/l.
Take inventory of Supplements and Medications
Make sure you are only taking those medications and supplements that are absolutely necessary for your body.
Supplements AND medications must be processed through the liver which can increase demand on your body.
Some medications you may need to continue even if they are potentially causing increase demand but the same may not be true with all supplements.
You should also try to avoid sketchy weight loss supplements or supplements that come from overseas.
Taking supplements such as B12, a multivitamin, fish oil, etc. should not be an issue.
Clean Up Your Diet
That means eating more fruits and vegetables!
Even if your liver issues are not caused by insulin resistance you can bet that eating excess sugar or refined carbs will definitely NOT be helping your issue.
Once the liver is slightly damaged it becomes susceptible to other potential causes of damage.
If you have non-alcoholic fatty liver disease you can be sure that excess alcohol consumption is NOT going to help your liver out.
Stick to these tips:
- Consume plenty of fresh and whole fruits and vegetables (19) (a rich source of antioxidative vitamins like B carotene and Vitamins C & E)
- Avoid refined carbohydrates (bread, pasta, bagels, etc.)
- Avoid refined sugars (especially sugary drinks such as flavored coffee, and sodas)
- Avoid alcohol 100%
- Avoid fast food
- Consume walnuts (a rich source of a-linoleic fatty acid)
While some supplements may potentially be damaging to the liver, others may offer considerable help.
One such supplement is Milk Thistle.
In various studies, milk thistle has been shown to work as an antioxidant in the liver, protect the liver against genomic injury, increase hepatocyte protein synthesis and decrease the activity of tumor promoters (20).
In animal studies (21), silymarin (the active ingredient in milk thistle) has been shown to reduce liver injury caused by Tylenol, iron overload, alcohol, and other causes.
With this in mind, milk thistle may be considered in many individuals with elevated liver enzymes.
Abnormalities in liver function tests should never be ignored.
If you have been identified as having an elevation in liver enzymes then you should go to work to find the root cause.
Whenever possible address and treat this condition and try to lower your AST and ALT levels as much as possible with treatment.
Now I want to hear from you:
Are you suffering from an elevation of AST and ALT?
Do you know why?
Leave your comments below!
References (Click to Expand)