Liver Function Tests – Understanding Your Blood Test Results

Dr Sandra Cabot and naturopath Margaret Jasinska run through what it means when your liver enzymes are raised in a blood test. Enzymes are meant to be inside the liver, so when they are raised it indicates that your liver is damaged and that the enzymes are leaking out of the liver and into the bloodstream. They discuss the different liver enzymes and the causes of liver inflammation and teach you how to understand your blood test results.

Listen to my podcast and leave a comment below if you have any questions.

DR CABOT: Hello, everyone. Today we’re talking about a fascinating subject – that is your liver – and how to understand the blood tests you may have to check your liver.

And we’re joined by Margaret Jasinska, our wonderful naturopath. Hi, Margaret.

MARGARET: Hi, Dr Cabot. And you are the Liver Doctor. So, this IS your topic.

DR CABOT: It is! Well, I’m the Liver Queen. I’ve been called the “Liver Queen” by other doctors too, because I’ve written so many books on the liver and, you know, I love the liver. I think it’s such a wonderful organ, in that it’s easy to treat. You get good results with patients. You can reverse many types of liver disease. Indeed, the majority of liver diseases. So, it’s a very satisfying part of medicine to practice. And it’s very important that people have an annual blood test to check their liver function because liver problems are very common. Probably the most common one we see today is fatty liver. Also, we see a lot of people who have adverse reactions to some prescribed medications and people who like to drink a little bit too much. And we see a lot of autoimmune liver problems, as well. And, of course, we have a lot of viral infections of the liver. So, the liver is prone to damage from many causes.

MARGARET: Yes. And also gut issues. People with gut problems, inflammatory bowel disease, celiac disease, irritable bowel, chronic diarrhea. Conditions that inflame the gut lining can compromise the barrier and excess gut wastes arrive at the liver and can inflame it and cause elevated liver enzymes, also.

DR CABOT: Yes. And that’s often not picked up as a cause. Sometimes patients will be wrongly accused of being a closet alcoholic. I’ve had a lot of patients said, “Well, my doctor told me to give up drinking, but I just drink tea. I’m a teetotaller and I was offended.” So, often the cause of liver inflammation is not picked up. And as Margaret said, it could be your gut that is leaky, that’s causing the problem.

So, when we do a blood test for liver function, what we’re testing is primarily your liver enzymes. And they are the enzymes that are inside your liver cells and they perform all the wonderful metabolic functions that your liver performs; like manufacturing protein, breaking down toxic chemicals, building antibodies, helping your immune system to function better.

So, the liver’s very, very busy and it needs these enzymes inside its liver cells to function. And so, these liver enzymes should, generally speaking, be less than 50 in a blood test.

MARGARET: Yes. They vary a little bit. And different labs, some less than 40. Some even say less than 35. But if you have an elevated liver enzyme, it will be in bold on your test result and there will be an asterisk next to it. And there might even be a little explanation as to what the common causes could be.

DR CABOT: Yes. And the enzymes we look at are abbreviated to AST, ALT, GGT and Alk Phos. So, there’s 4 enzymes we look at. And the GGT is the one that often goes up first in people who have taken too much paracetamol or otherwise had an adverse reaction to a medication or if they’re drinking too much alcohol. But the GGT enzyme can be elevated from any type of liver damage.

The enzyme ALT that typically becomes elevated in people with a fatty liver.

MARGARET: We see it a lot, then.

DR CABOT: Yeah, we do. And these raised liver enzymes, what do they mean? Well, they mean that the enzymes are leaking out of your liver cells into your bloodstream. So, they’re too high in the bloodstream. Now, this in itself won’t cause you any harm. Having raised liver enzymes in your blood won’t damage you. But what it’s a sign of is that your liver cells are damaged. They’re being inflamed, so they get leaky and they leak the enzymes outside into the bloodstream. So, it’s a sensitive indicator of liver inflammation.

So, we see people with very slight elevation of their liver enzymes to people who have very, very high. And I have one particular patient who’s an elderly lady in her 70s, and she has severe fatty liver disease and it goes up and down with her diet. She’ll be good for 3 months and her liver enzymes will be almost perfectly normal. And then she’ll go on a carbohydrate binge and she’ll eat a lot of gluten and a lot of processed food. And her liver enzymes will go up to above 1000 for GGT.

MARGARET: Does she have cirrhosis, though?


MARGARET: Okay. Well, that’s good! Because the longer you’ve been harming your liver, the more likely it is to form scar tissue in your liver.

DR CABOT: Yes, correct!

MARGARET: S, she’s lucky she’s been getting away with that for a while.

DR CABOT: Yes. Well, it just shows you that the liver is a very forgiving organ and you can really repair damage very well with nutritional medicine. Not that I advise you to do what this lady does, and go on binges. But…

MARGARET: She can’t help herself.

DR CABOT: No, she loves carbohydrates.

MARGARET: Addiction is addiction. Like people try to drink less alcohol, but they can’t always.

DR CABOT: It’s very difficult, but we can try. And she takes the Livatone Plus, and that’s helped her a lot. The Livatone Plus has been a godsend for her.

So, the liver enzymes will tell you whether your liver is inflamed. Very good test.

MARGARET: So, Dr Cabot, alkaline phosphatase. That particular liver enzyme doesn’t always relate to something happening in the liver. It can be elevated if there is a bone condition.

DR CABOT: Correct! Yeah. It’s an enzyme that is also found in bone and in people who have got a high bone turnover, that can be elevated. So, it can be a sign of vitamin D deficiency or other bone disease, as well.

MARGARET: What about cancer metastasis to bone?

DR CABOT: Yes. Anything that’s disturbing the bone. But it’s not that common to go up in liver problems, but it can. There can be an elevation of all the liver enzymes. And so, it’s good to have your liver enzymes checked every 12 months. Your AST, your ALT, your GGT and your Alk Phos.

Now, the other thing we test in a liver function is your protein level; the amount of protein in your blood. And that varies in the range from 60 to 82. And the liver manufactures a lot of the proteins in your body. So, it’s very important to check that you have enough protein.

MARGARET: Yes. So, a lot of people mistakenly think that that test is an indicator of whether they are eating enough protein or not. “So, I’m a vegan. I eat oatmeal, fruit and salads, and that’s all I eat. But I had this blood test. I’m getting enough protein.” But this test is specifically about the proteins that your liver manufactures. And so, they’re binding proteins, they’re blood clotting proteins. They’re not an indicator of whether you are consuming enough protein.

DR CABOT: Yes. And you’re not a vegetarian. It sounded like you said, you’re a vegetarian.


DR CABOT: Margaret, she’s a carnivore. She eats a lot of meat.

MARGARET: I’m Polish. I wouldn’t be alive. My ancestors ate meat. Much of the year the ground is covered in snow.

DR CABOT: Yes, I know. Well, look, we won’t go there. That’s a whole other topic. But, yeah, the protein that we measure in your blood is really a sign of your liver function. Is your liver making enough protein?

MARGARET: Yes. And so, with some serious liver conditions, protein production can be compromised. And so that figure can be below normal.

DR CABOT: Yes. And really, the first protein that will go low, if you have liver disease, is your albumin. And that’s a specific protein that we measure in a liver function test. And the albumin level should be between approximately 40 to 50. Now, in people who are getting cirrhosis, their liver cannot make enough albumin. But also, they’re losing albumin from their body and it leaks into their abdominal cavity. So, they get low blood albumin and they will develop ascites, which is very unpleasant.

So, if you’re starting to get low albumin, that’s a sign that your liver is quite sick and you really need to take it seriously. But as we said, the good news is you can reverse most types of liver disease. But don’t wait until you’ve got end stage cirrhosis.

MARGARET: And so, it also says, Bili here. B-I-L-I.


MARGARET: Which is short for biliruben.

DR CABOT: Biliruben!

MARGARET: So, that’s something else that is checked in a liver function test.

DR CABOT: Yes. Well, that is the bile pigment. And the liver has to eliminate that through the bile into the feces. That’s why your feces are a dark color. And in people who have sluggish bile flow, they will get an elevation of their bilirubin. And if it’s very, very high, they will get jaundice. They’ll get that yellow discoloration in their eyes.

MARGARET: Yes. However, mildly raised bilirubin is actually quite common. Just if it’s a few points above normal. And it’s most commonly caused by something called Gilbert’s syndrome, which is just an inherited condition, which is common in Europeans, where there’s just a compromised ability to excrete the bilirubin. It’s really of no consequence. We have quite a few articles about Gilbert’s syndrome on our Liver Doctor website. And for most doctors, they don’t even mention it to their patient. So, if I see one of my patients with slightly elevated bilirubin, I say, “Oh, it looks like you’ve got Gilbert’s syndrome!” And they say, “What’s that? My doctor’s never mentioned that to me.”

DR CABOT: “What’s Gilbert got to do with it?” Well, Gilbert was a French doctor, and they often call it Gilbert’s syndrome because it was Dr Gilbert who first described it. And, yeah, it’s quite common. And sometimes people with Gilbert’s syndrome will say that their liver is a little bit sensitive to medications and they can’t drink very much.

MARGARET: Exactly! It depends. If they follow a healthy diet and lifestyle, they’ll be fine. But if they eat poorly, if they drink a lot, if they’re on a lot of medication, don’t rest, don’t sleep, don’t exercise, then their health can suffer and they can become visibly jaundiced.

DR CABOT: And people with Gilbert’s syndrome often feel better taking a good liver tonic regularly, such as the Livatone Plus – just helps to support their lazy enzymes. Because that’s what Gilbert’s syndrome is; having a few lazy liver enzymes. But it’s genetic and it’s nothing to worry about. It’s not a disease. It’s just a variation.

Okay, so have your liver function checked with the blood tests every 12 months. And if your liver enzymes are elevated, you should have a liver ultrasound to see if you have a fatty liver or any gallstones or any tumors in the liver. And we should repeat the liver function 4-6 months later to make sure the liver enzymes have come down.

So, there you go! Now you understand your blood tests for liver function. We hope you’ve enjoyed this session. Thanks for listening.

MARGARET: Thank you, everybody. Bye bye.