Blood tests for liver function
Some of the standard or routine blood tests that your doctor will order to check “liver function” are in reality only able to detect liver damage. These tests may not be sensitive enough to accurately reflect whether your liver is functioning at its optimum level.
These tests will usually be abnormal in significant liver disease or liver distress; however, they can still give normal readings in some cases of mild liver disease. This is why imaging tests of the liver and gallbladder, such as ultrasound scans or CAT scans or MRI scans are important. These imaging tests can determine the degree of liver disease and if there are any tumours, cysts, gallstones or fatty accumulations which change the texture of the liver.
Thankfully it is often possible to return abnormal liver function tests to normal with our dietary program.
A routine blood test for liver function will be processed by an automated multi-channel analyser, and will check the blood levels of the following:
- Total Bilirubin
The normal range is 0 to 20 umol/L or 0.174 to 1.04 mg/dL. This test measures the amount of bile pigment in the blood. If blood levels of bilirubin become very elevated, the patient may have a yellow colour to the skin and eyes and this is known as jaundice.
- Liver Enzymes
AST (aspartate aminotransferase), which was previously called SGOT, can also be elevated in heart and muscle diseases and is not liver specific.
The normal range of AST is 0 to 45 U/L
ALT (alanine aminotransferase), which was previously called SGPT, is more specific for liver damage.
The normal range of ALT is 0 to 45 U/L
ALP (alkaline phosphatase) is elevated in many types of liver disease, but also in non-liver related diseases.
The normal range of ALP is 30 to 120 U/L
GGT (gamma glutamyl transpeptidase) is often elevated in those who use alcohol or other liver-toxic substances to excess.
The normal range of GGT is 0-45 U/L.
Why do all or some of these enzymes become elevated in cases of liver disease?
Normally these enzymes are mostly contained inside the liver cells; they only leak into the blood stream when the liver cells are damaged. Thus, measuring liver enzymes is only able to detect liver damage and does not measure liver function in a highly sensitive way.
- Blood Proteins
These proteins are manufactured by the liver and are measured in the blood test for liver function.
Their normal ranges are as below:
- Total protein: Normal range is 60 to 80g/L or 6 to 8g/dL
- Serum albumin: Normal range is 38 to 55g/L or 3.8 to 5.5g/dL Serum albumin is a good guide to the severity of chronic liver disease. A healthy liver manufactures plenty of albumin and falling levels of blood albumin show deteriorating liver function.
- Globulin protein: Normal range is 20 to 32g/L or 2 to 3.2g/dL. Blood levels of globulin may be abnormal in chronic liver disease. Elevated levels of globulin proteins in the blood usually mean excessive inflammation in the liver and/or immune system. Very high levels may be seen in some types of cancers.
Interpreting your blood test results
Doctors generally look first at the level of the liver enzyme GGT. Generally speaking in “normal liver function tests” the level of GGT is not greater than 45.
If your GGT is greater than 100, the doctor will look at the levels of the other liver enzymes to try and work out possible causes of liver damage. Let’s take a look at some possible combinations of abnormally high liver enzymes and what that could mean.
If your GGT is above 100, and your ALT is less than 80 and your ALP is less than 200
This could mean that:
- You are drinking too much alcohol
- You are taking recreational drugs such as ice or heroin
- You have diabetes
- You have a fatty liver
- You have very high levels of the blood fat called triglycerides
- You are taking certain prescribed drugs that have stimulated your liver to make more enzymes for example – barbiturates, benzodiazepines, anticonvulsants, warfarin, tricyclic antidepressants, paracetamol, pain killers or immunosuppressants.
Note: in some people it is normal for GGT levels to be as high as 120, with no liver problems being found.
If your GGT is above 100, and your ALT is less than 80 and your ALP is above 200
This could mean that:
- The flow of bile is being slowed down or obstructed and this could be from a gall stone in the bile ducts, very inflamed bile ducts or a tumour inside the liver or a tumour outside the liver which is pressing on the bile ducts.
- Excess drugs or alcohol can slow the flow of bile
- Scarring of the liver (known as cirrhosis) can distort the bile ducts and cause slowing/obstruction to the flow of bile.
- You have liver disease plus bone disease, as the enzyme ALP can also be elevated by some bone diseases
Note: when the flow of bile is obstructed or slowed, the level of bile (bilirubin) becomes elevated in the blood to above 20 and the patient may turn yellow (jaundiced).
If your GGT is above 100, and your ALT is above 80 and your ALP is less than 200
This could mean that:
- The liver cells are inflamed by certain viruses such as the Hepatitis A, B or C viruses or the glandular fever virus (Epstein Barr Virus).
- You are taking liver toxic drugs or drinking excess alcohol
- You have a fatty liver
If your GGT is above 100, and your ALT is above 80 and your ALP is above 200
This could mean that the liver cells are damaged plus there is slowing or obstruction to the flow of bile and this can occur in the following liver diseases:
- Acute hepatitis from viral infections or drug or alcohol toxicity
- Chronic (long term) hepatitis from viral infections, alcohol excess or autoimmune diseases
- Tumours inside or near the liver which obstruct the flow of bile
- Scarring of the liver (cirrhosis)
Note: in alcoholic liver disease the level of the other liver enzyme AST is often elevated to high levels as well, and is usually higher than the level of ALT.
Non-alcoholic fatty liver disease
Non-alcoholic fatty liver disease (NAFLD) represents the most common form of liver disease and is considered to be the liver manifestation of Syndrome X (the metabolic syndrome).
Within the degrees and types of NAFLD, simple fatty accumulation (hepatic steatosis) is not considered to be highly dangerous in itself although it can lead to weight excess and diabetes. However the more severe form of fatty liver known as non-alcoholic steato-hepatitis (NASH) may progress to cirrhosis and liver failure. The distinction can be made by liver biopsy.
There is not complete agreement on the criteria for diagnosis or the features used for grading and staging lesions. Both types of fatty liver disease are reversible and the key is earlier diagnosis and the use of nutritional medicine.
For the diagnosis of fatty liver, physical examination, blood tests, imaging techniques and liver biopsy are being used.
The following tests are generally recommended
- If the liver enzymes are only slightly elevated and there are no physical signs of liver disease, blood tests for liver function can be done every 6 months. If the liver function does not deteriorate and the patient remains well there is no need for liver biopsy. The liver function blood test should continue to be checked every 6 months.
- An ultrasound scan of the liver should probably be done every year.
If there is any concern that the degree of fatty liver damage is rapidly progressive, or that there could be other undetected liver disease present, a liver biopsy should be seriously considered.
I personally think that if you follow our dietary principles, and your liver function and wellbeing are improving, you do not have to panic and rush into a liver biopsy.
If despite your best efforts to heal your liver with nutritional medicine, your liver function and health are deteriorating then a liver biopsy is indicated. At the end of the day it will be your decision and you must also listen to your own doctor’s advice.
Fibroscan uses ultrasound to create waves and measures the speed at which these waves are reflected by the liver. The speed of the wave determines the degree of liver stiffness. The more scarred the liver the stiffer it becomes and the stiffer the liver the quicker the waves are reflected.
Fibroscan was invented to assess the amount of scarring (fibrosis) present in the liver which develops in cirrhosis. It does this by measuring the stiffness or elasticity of the liver.
Results are presented as a number in kilopascals (kPa). The higher the number, the stiffer and thus more scarred the liver.
Until several years ago, the only accurate way of finding out how much scarring was in a liver was by having a liver biopsy. Blood tests can tell you if you have liver inflammation or infection with viruses, but they can’t show how damaged your liver tissue is.
Ultrasounds and CAT scans often don’t show the difference between liver scarring damage caused from chronic liver diseases such as viral hepatitis, iron overload, alcoholism or fatty deposits. A fibroscan will accurately detect the amount of scarring, which is the most important thing as it predicts and monitors liver cirrhosis which can lead to liver failure, irrespective of the cause.
Now we have the Fibroscan test to do this in a safe way. The fibroscan does not expose you to needles or irradiation or drugs and unlike a liver biopsy is risk free!
This simple ten-minute test can detect liver damage but it does have some limitations. For example, the Fibroscan is very good at detecting a healthy normal liver or a liver with severe extensive fibrosis (cirrhosis) but it is much less sensitive at detecting mild or moderate liver fibrosis. Fibroscan will only measure liver fibrosis and will not help to diagnose the cause of the liver damage. In these cases a Liver biopsy may still be necessary.
Fibroscan is very useful for following the progression of liver fibrosis over years and because it is non-invasive can be repeated regularly without risk (unlike liver biopsy).
In the early stages of liver disease, symptoms are uncommon and vague and conventional ultrasounds may not be very helpful. It is often difficult for people to know whether their liver is significantly damaged or not until it is in the advanced stages of scarring which is cirrhosis. By the time you notice any symptoms of liver disease, the damage may be too great to reverse. Fibroscan helps with early and accurate detection of liver disease which improves a cure as the liver is able to repair and regenerate itself.
New test for Cirrhosis – Fibrosure or Fibrotest
A new test to determine if fibrosis (cirrhosis) is present in the liver is now available and is a breakthrough for patients with liver disease. This new test is called a Fibrosure or Fibrotest.
In the past, the standard test to determine the physical state of the liver tissue was a liver biopsy. During a liver biopsy a fine needle is pushed into the liver and a sample of liver tissue is taken and then sent to a laboratory where a pathologist examines it under a powerful microscope. The pathologist can see if the liver cells are damaged and how much scar tissue is present in the liver tissue. If there is a lot of scar tissue the patient is diagnosed with cirrhosis. The amount of scar tissue determines the stage of cirrhosis from mild to severe.
There are several problems and limitations with a liver biopsy
- Only a small area of the liver is sampled – thus the biopsy may miss other parts of the liver which are more or less diseased
- There are risks to the procedure such as bleeding and infection
- The procedure is unpleasant, scary and incurs some discomfort.
Thus it’s easy to understand why a new non-invasive blood test to check for cirrhosis is a huge welcome relief for patients with chronic liver disease.
The Fibrosure test is a blood test which measures several different naturally occurring substances in the blood which give an indirect indication of chronic liver inflammation and through a mathematical calculation this is converted to a score for fibrosis. Fibrosis is the same as scarring. Scar tissue consists of hard fibrous tissue. Cirrhosis is caused by scar tissue building up in the liver.
The Fibrosure blood test measures the amount of the following substances in your blood:
Alpha 2 macroglobulins (normal range = 110 to 276 mg/dL) Haptoglobulin (normal range = 34 to 200 mg/dL) Apolipoprotein A-1 (normal range = 110 to 205 mg/dL) Bilirubin total (normal range = 0 to 1.2 mg/dL) GGT (normal range = 0 to 60 IU/L) ALT (normal range = 0 to 40 IU/L)
No need for you to remember these parameters, they are just included in case you want to research them further. The important thing is that these values are combined mathematically to create a score for you which will determine the following:
Fibrosis Score (normal range = 0 to 0.21) – you want this to be low Fibrosis stage from 1 to 5 – you want this to be low Necro-inflammatory activity score (normal range = 0 to 0.17) – you want this to be low Necro-inflammatory activity grade – this is graded from mild to severe – you want this to be mild
The Fibrosis score and stage determine the amount of scarring in your liver. The Necro-inflammatory activity score and grade determine the amount of inflammation in your liver and this is important because chronic inflammation in the liver causes the scar tissue to build up and destroys healthy liver cells.
If we can reduce the inflammation with nutritional medicine we can reverse some of the damage and even better, prevent the scar tissue from increasing anymore. Remember that of all the organs in the body, the liver is most able to repair and regenerate itself. For more information see my book The Liver Cleansing Diet.
For information about Liver Biopsy, click here
The Breath Test – is a possible alternative to liver biopsy
A test known as the 13C-caffeine breath test has been developed by researchers at the University of Sydney and Concord Hospital, which is able to detect fibrosis (scarring) in the liver. It has been used in patients with hepatitis B and has been shown to accurately detect fibrosis when compared to the patient’s liver biopsy results. In a study of 33 patients with hepatitis B who had different degrees of fibrosis, the breath test was found to accurately predict severe liver scarring which leads to cirrhosis of the liver.
How is the breath test done?
The patient must fast overnight and then drinks a caffeine beverage containing a special carbon tag. The patient’s breath is analyzed by a process known as continuous flow isotope ratio mass spectrometry. The greater the degree of liver scarring the less carbon will be detected in the breath; this allows accurate quantification of the degree of liver scarring.
Researchers are predicting that this new breath test can be used as an accurate way to assess the degree of liver scarring in people with fatty liver. The test is already being used at Concord Hospital in Sydney in selected patients to avoid liver biopsy but is not yet generally available. The new breath test will be good news for the future because liver biopsies are expensive and their interpretation can be inaccurate. The breath test is of great practical value because a significant number of cases of fatty liver will progress to liver scarring and fibrosis (cirrhosis) and if the breath test shows that this is happening, a more aggressive approach to treatment is essential.
Imaging Techniques to visualize the Liver
Ultrasound scans of the liver
Ultrasound scans are very useful to detect fatty changes in the liver and are inexpensive and do not expose you to any radiation or danger. If fatty changes are found in more than 30% of liver lobules a diagnosis of fatty liver is made.
The ultrasonic features of a fatty liver include:
- Bright pattern
- Vascular blurring
- Deep attenuation
It is useful to compare the brightness of the kidneys to the liver and if the liver is much brighter it is fatty. Kidneys do not develop fatty changes.
The sensitivity of ultrasound scans in the diagnosis of fatty liver approaches 100 percent. The correlation of fatty liver in ultrasound scans and liver biopsy tissue examination is 73.6%. Therefore, the degree of fatty infiltration seen in ultrasound scans is significantly correlated with degree of fatty accumulation of liver.
Cat scans and MRI scans of the liver
CAT scan of upper abdomen
Non-enhanced CAT scans and MRI scans are comparable in their estimation of the degree of fat accumulation in the liver (hepatic steatosis). However for detecting mild grades of fatty liver, MRI scans are better than un-enhanced CAT scans. CAT scans expose you to significant radiation whereas MRI scans do not.
Magnetic Resonance Elastography or MRE
Researchers at The Mayo Clinic have invented a diagnostic imaging test which is able to detect very early stages of liver disease. It is called Magnetic Resonance Elastography or MRE and it is now being used at Mayo Clinic for patients who are at risk for liver diseases. MRE measures the elasticity of the liver and can detect abnormal hardening or stiffness of liver tissue – in a way you could say that MRE allows doctors to “feel” the liver by imaging it. Scar tissue is very fibrous and makes the liver hard whilst healthy liver tissue is elastic and makes the liver soft and MRE can easily detect the difference.
MRE is extremely accurate – its sensitivity for diagnosing liver fibrosis is 98 percent and its specificity level (absence of false positives) is 99 percent.
The MRE (“liver elastogram”) provides color images of the liver that look amazing! To see pictures of liver elastograms visit www.mayoclinic.org/magnetic-resonance-elastography/
The wonderful thing about MRE is that it can spare some patients the need for a liver biopsy. Such early and accurate diagnosis of liver disease allows doctors to initiate early and specific treatment before it progresses to cause irreversible damage.
Damage to liver cells by fat, toxins or infections etc, causes inflammation, which can lead to hard scar tissue or fibrosis. A liver that has developed widespread fibrosis is firmer, and if the condition progresses to cirrhosis, the liver can become almost rock-hard. The vital thing is, if detected early, fibrosis of the liver can in many cases be reversed. If the scar tissue progresses to widespread cirrhosis, the condition is usually irreversible. About 50% of patients diagnosed with cirrhosis will die within five years unless they receive a liver transplant.
Having an MRE test done is not unpleasant – it does not involve needles, physical pain, deep palpation or radiation. A small circular drum-like device is strapped around the abdomen before going into the MRI machine. The machine vibrates in different rhythms and generates shear waves that pass into the liver.
Many patients don’t have a sufficiently high probability of liver disease to justify the risk of an invasive liver biopsy. As well as those with fatty liver, this includes the hundreds of millions of people in the world who have hepatitis B and C. Because only a small percentage of these individuals will develop progressive liver fibrosis, many could be candidates for an MRE screening test.
Other important blood tests to have if you have been diagnosed with a fatty liver
- Fasting blood sugar and insulin levels – if these are elevated it is wise to have a 2-hour Glucose Tolerance Test (GTT)
- Glycosylated hemoglobin – abbreviated to GHB or HbA1c – this test shows the average level of sugar (glucose) that has been present in your blood over the previous 3 months
- Fasting blood fats (lipids) – cholesterol and triglycerides
- A serum ferritin test to check the level of iron in your body. If your ferritin level is elevated you should have further blood tests known as “serum iron studies”. You may also need a blood test for the genetic disease of iron overload called hemochromatosis. Excess iron in the liver can lead to severe liver disease. If you have a fatty liver PLUS excess levels of iron in your liver, these two factors will work together to accelerate the amount of liver damage.
- If you have a fatty liver and suffer with bowel or digestive complaints, it is worthwhile having a blood test to see if you are intolerant to gluten. Gluten is the protein found in specific grains namely wheat, oats, rye and barley. Some people are genetically prone to poor health if they eat gluten. The most accurate blood test to ask your doctor for is “test your genotype for the genes that predispose to gluten intolerance”. If you have these genes, you may find that your liver health and immune system improve greatly, by avoiding gluten containing foods.
Elevated insulin levels stimulate your liver cells to produce abnormally large amounts of cholesterol. In those with Syndrome X there will be low levels of the good HDL cholesterol, and excessively high levels of the bad LDL cholesterol.
Around 80% of the body’s cholesterol is made in the liver and the cells of the small intestine, and only around 20% comes from the diet. If you eat more cholesterol your liver will make less and if you do not eat any cholesterol, your liver will manufacture all the cholesterol that you need. If you have a healthy liver, the balance of the good cholesterol (HDL) and the bad cholesterol (LDL) will be favourable in the vast majority of cases. It is not so much the avoidance of dietary cholesterol that is important, but the state of your liver that is important.
Fasting levels of the blood fats
You will need to have your blood taken in the fasting state, which means that you should not eat/drink anything apart from pure water, for 12 to 14 hours before the blood is taken. It is easiest to fast overnight and have your blood taken before breakfast.
|Fats||Normal range(in mmol/L)||Normal range (in mg/dL)|
|Total cholesterol||3.9 to 5.5||148 to 209|
|Triglycerides||0.1 to 2.0||9 to 177|
|LDL cholesterol||0.5 to 3.5||19 to 133|
|HDL cholesterol||1.0 to 1.9 (males)||38 to 72 (males)|
|HDL cholesterol||1.2 to 2.3 (fremales)||46 to 87 (females)|
Total Cholesterol divided by HDL gives a ratio which is predictive of your risk of heart disease
|Ratio (Cholesterol divided by HDL)||Risk|
|2.5 to 3.5||below average (desirable)|
|3.5 to 5.5||average|
|5.6 to 8.3||high|
Triglycerides are lightweight small fatty particles that have only a very small amount of protein attached to them. Most of the triglycerides are stored as fat in your fat deposits and a small amount is sent to the muscle cells for energy. The triglyceride fats are manufactured in the liver, which converts them to very low-density lipoproteins abbreviated to VLDL. High levels of triglycerides and VLDL will not only increase weight gain and fatty liver, they will increase your risk of cardiovascular disease.
Those with Syndrome X have a build up of “triglyceride – rich – lipoproteins” (fatty protein particles) in the blood after eating. High blood levels of insulin cause the liver to produce very low-density lipoprotein triglyceride (VLDL-TG). This is very dangerous and predisposes to fatty liver, atherosclerosis, and obesity.
Today, many people have become obsessed with cholesterol and think it is the main predictor of heart disease. Indeed many overweight people never bother to have their triglyceride levels checked, often because their doctor does not think it is important. However, high triglyceride levels by themselves, irrespective of cholesterol levels, are a potent risk factor for heart disease. Indeed high triglyceride levels are just as important as smoking, obesity and high blood pressure in increasing your chances of heart disease and strokes. High triglycerides make your blood thick and sticky so that it does not flow freely around inside your blood vessels – this increases the risk of blood clots. Fish oil supplements are able to reduce triglyceride levels and reduce the risk of blood clots.
A study at Harvard University way back in 1966 showed that very high triglyceride levels could be reduced greatly with a very low carbohydrate diet. A diet high in refined carbohydrates (and low in protein and fat), will increase insulin levels, which will cause an elevation in the triglyceride levels. Conversely a diet low in carbohydrates, and particularly low in refined carbohydrates, will lower triglycerides.
Normal triglyceride levels = 0.1 to 2.0mmol/L or 9 to 177mg/dL
The lower they are within this normal range the better off you are.
Make sure that you are fasting (do not eat/drink anything but water for 12 to 14 hours before the blood test), when you have your blood taken to measure the triglyceride levels. This is because triglyceride levels can be temporarily much higher just after eating.
Blood Sugar Level (BSL)
Your fasting blood sugar (glucose) level should be below 6.1mmol/L (110mg/dL).
If it is above this level, this means that insulin is starting to lose control over your blood sugar levels. This is a sign of insulin resistance which causes Syndrome X and fatty liver
Glucose Tolerance Test
The Glucose Tolerance Test (GTT) measures the tolerance of an individual for an extra load of administered glucose. If your tolerance for this extra load of glucose is normal, then your blood levels of glucose will remain within the normal range. If your tolerance for this extra load of glucose is impaired, your blood sugar levels will become higher than the normal range (see table X).
If you have impaired glucose tolerance, this will be because you have insulin resistance, meaning that your insulin is incapable of controlling your blood sugar levels. If your blood sugar levels become even higher, you will be classed as a diabetic, which could be due to severe insulin resistance or insulin deficiency (pancreatic failure).
The GTT will only be accurate if you follow a relatively high carbohydrate diet (200 grams daily) for 4 days before the test.
The GTT measures your blood sugar (glucose) levels after you ingest a test dose of glucose. The blood sugar levels are measured over a period of several hours, depending on whether the doctor has ordered a 2-hour GTT, or a GTT which goes for longer.
Subtle abnormalities in the GTT often occur in those with fatty liver and/or Syndrome X, a long time before the onset of diabetes.
Blood Sugar Levels during GTT as measured in mmol/L
|Time||Normal Levels||Impaired Glucose Tolerance||Diabetes|
|Fasting||3.6 to 6.1 (65 to 110mg/dL)||6.1 to 6.9 (113 to 124mg/dL)||over 6.9 (over 124)|
|2 hour||Less than 7.1 (128mg/dL)||7.2 to 11.0 (130 to 198mg/dL)||over 11 (over 198)|
The one-hour blood glucose level is not always reported, but generally speaking a level over 9.0mmol/L (162mg/dL) is considered abnormal, and is indicative of impaired glucose tolerance.
Ideally insulin levels should be tested along with the blood glucose levels, at least for the first 2 hours of the GTT. The fasting level of insulin should be checked, as well as the insulin level 2 hours after the patient ingests the glucose. The 2-hour insulin level is abnormally elevated if it is 1.5 times your age, up to the age of 50.
Using this method a 2-hour insulin level of 75 would be abnormally high for any person.
Serum Insulin Levels
It is a worthwhile endeavour to measure blood insulin levels, as it is the high insulin levels, which are the cause of Syndrome X and many cases of fatty liver.
A laboratory accustomed to measuring insulin levels should do the testing of your insulin levels. The specimen of blood should be frozen and the test must be completed within 24 hours of taking the blood. If these procedures are not followed the results may be inaccurate.
Excessive blood levels of insulin (hyperinsulinemia) are diagnosed by finding an elevated fasting blood insulin level and/or by finding elevated insulin levels two hours after giving the patient a 75-gram dose of pure sugar (glucose).
Generally speaking, if your fasting insulin level is over 10mU/ml, you probably have some degree of Syndrome X, meaning that you are developing insulin resistance. The greater your fasting insulin level is over 10, the greater is your insulin resistance. If we use 10 as the upper limit of normal for fasting insulin levels, a result of 30 would mean that it requires 3 times the normal amount of insulin to keep your blood sugar levels at their current value.
Some laboratories will set the upper normal limit of fasting insulin levels as high as 20, but this will miss some people with insulin resistance, who have not yet lost control of blood sugar levels.
Normal insulin levels during a GTT are considered to be the following:
|Time||Normal Serum Insulin (in uU/ml or mu/L)|
|Fasting||less than 11 (many labs will report anything below 20 as normal)|
|1 hour||9 to 70|
|2 hour||5 to 60|
|3 hour||1 to 24|
Some laboratories have different “normal ranges” for serum insulin, which are higher than the above values, and may miss some people with Syndrome X. For example some laboratories will state that insulin levels below 70 are normal, while insulin levels above 80 indicate insulin resistance. They qualify this by saying that insulin levels in between 70 to 80 are in a “grey area” and may indicate insulin resistance. I think the lower levels in the table are more realistic, and if used for evaluation, will not miss as many people who are in the early stages of Syndrome X.
Because of the wide variation in insulin levels during a GTT, most endocrinologists evaluate the fasting insulin level only, and if this is not raised a diagnosis of insulin resistance is thought to be unlikely.
Glycosylated haemoglobin levels
Glycosylated haemoglobin levels can be abbreviated to Hgb A1 or HbA1c or GHB, which is helpful to know if you are looking at your own blood test results.
The level of GHB measures the average amount of sugar that has been present in your blood over the previous 3 months.
The normal laboratory range of GHB is 4 to 6%.
The lower your level of GHB, the better you will be, as far as blood sugar control is concerned.
In type 2 diabetics good blood sugar control is present when the GHB is less than 7%. Diabetics who keep their GHB levels close to or below 7%, have a much better chance of preventing diabetic complications, such as diseases affecting the eyes, kidneys and nerves, compared to those diabetics whose GHB levels are 9% or greater.
You should aim for your GHB level to be at the lower limit of the normal range, and certainly not towards the upper limit. If your GHB level is above the normal range you are certainly suffering with the insulin resistance of Syndrome X, and indeed may be pre-diabetic or even diabetic.
Serum iron studies
If you have fatty liver disease it is worth checking that your body does not contain excess amounts of the mineral iron. High levels of iron can inflame the liver and if the iron levels are very high, can increase the risk of severe liver disease such as cirrhosis. The excess iron will work synergistically with the excess fat in the liver to increase the amount of liver damage; thus it is important to remove the excess iron from the body to protect your liver.
This can be safely and effectively achieved by having some of your blood removed regularly and this procedure is called venesection. Your blood should be removed on a regular basis until your iron levels become normal and this can be arranged by your local doctor. You can also achieve a desirable reduction in your body iron levels by becoming a regular blood donor.
If you have a blood test for iron studies this is what the results will look like:
|Iron||9.0 – 31.0µmol/L|
|Transferrin||2.0 – 3.7 g/L|
|TIBC||45 – 80µmol/L|
|Saturation||16 – 60 %|
|Ferritin||30 – 300µg/L|
If the levels of iron are high and the saturation is high you have too much iron in your blood, which could get into the liver and damage the liver. The ferritin parameter measures the total amount of iron stored in your body and if this is high, chances are that there is too much iron stored in your liver. High ferritin levels are also a sign of liver inflammation.
These statements have not been evaluated by the FDA and are not intended to diagnose, treat or cure any diseases.