HGH (human growth hormone) is an integral part of human body function. Normal growth and metabolism are largely dependent on it. Different levels of HGH will be present at different times in response to such things like exercise, sleep, emotional stress and diet.
Just like almost everything else that is responsible for balance and normal function, too much or too little can create serious problems. Excessive amounts of HGH during childhood will lead to giantism, while too little could very likely cause dwarfism. Unlike other problems that can arise as a result of excess or deficiency, both giantism and dwarfism can be treated if they are diagnosed early enough.
Insulin-like growth factor, also known as IGF-1 works in conjunction with HGH. With out IGF-1, the benefits of HGH would never be seen. Since the two work so closely together, it is safe to say that if the levels of HGH are abnormally high then so are the levels of IGF-1. There is a test available to measure the amount of IGF-1 in the blood stream, which is then used to gauge the amount of growth hormone being produced as well. This test is administered by submitting two blood samples, which should be taken on different days.
Why test for HGH?
As mentioned earlier, there are a multitude of illnesses that can be caused by unhealthy growth hormone secretions. In order to determine if symptoms of an illness are being caused by deficient or excessive production of growth hormone, tests must be conducted. Once such illness is acromegaly, which is usually indicative of an adenoma or a tumor in the pituitary. Testing must also be available during treatment with HGH injections in order to monitor the progress of the patient.
In order to ensure that test results are completely accurate, the individual being tested may be asked to stay relatively still for 15 to 60 minutes prior to blood being drawn for testing. The reason behind this request is that exercise and physical activity affect hormone production. Another form of interference would be certain medications that may need to be eliminated so as not to skew the results. These drugs include estrogen, like that found in birth control pills and corticosteroids. The patient must be sure to mention any kind of prescriptions or over the counter medication being taken before proceeding with this kind of testing.
How is it done?
More than one blood sample must be taken on different days, due to rapid changing levels of growth hormone. A test measuring IGF-1 levels may be taken in conjunction, as its levels change much slower. Before blood is drawn, the administering health professional should be informed of any disorders or medication being taken which can lead to bleeding at the site of the puncture.
Results of the test usually vary from lab to lab. The basic guideline followed is: For Men 0-5 ng/ml (nanograms per milliliter), women 0-10 ng/ml, and children 0-16 ng/ml. Above normal values on these test results mean above normal levels of HGH. These higher levels may indicate giantism or acromegaly, which are caused by GH producing adenomas or tumors in the pituitary. Such conditions are associated with an increase in IGF-1 levels as well. Increased levels of HGH can also be the result of conditions such as diabetes, kidney disease, even starvation. Unlike giantism and acromegaly, these illnesses are not related increased levels of IGF-1.
There are several methods used to determine whether hormone levels are normal or are causing a problem. Some examples are: growth hormone suppression tests, which measure GH levels before and after consumption of large amounts of sugar. Following a large sugar intake, levels should be low, if they continue to be high, acromegaly could be the problem. The growth hormone stimulation test measures GH levels before and after insulin is introduced. Post insulin growth hormone levels should, under normal circumstances, be higher if not, the patient may have to be treated for a GH deficiency.
Science continues to develop new more accurate tests in order to diagnose illnesses associated with growth hormone abnormalities. Until one test can be developed that can give us all the answers, scientists and physicians continue to employ multiple methods to ensure accuracy.
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