SHBG is short for Sex Hormone Binding Globulin.
This test is rarely ordered, which is unfortunate because it can give you a lot of information about the hormones in your body.
High levels can lead to symptoms of excess estrogen, excess thyroid, and low testosterone.
Low levels can lead to symptoms of low thyroid, low estrogen, and excess testosterone.
In this article, I will discuss how to interpret your SHBG test results, and list some common causes of elevated levels and low levels.
I will show how SHBG can be used to monitor your thyroid function if you are on thyroid medication.
I will also discuss some things that you can do to help you get your SHBG level back into the optimal range whether it is high or low…
SHBG is an acronym for sex hormone binding globulin.
It does what it sounds like it does – it binds up sex hormones.
Why is that important?
In order to understand this better we need to discuss how hormones work in general.
The vast majority of hormones in your body are bound to proteins in the bloodstream. This helps to stabilize the hormone so it can get to the targeted cells all over the body.
While it is bound, however, it is inactive and not available for the cells to use.
In order for the hormone to be active, it must break away from the protein. This makes it a “free” hormone and it can then enter the cells and turn on the cellular function it is designed to do.
This is called the Free Hormone Hypothesis.
The “free” hormones are therefore the “active” hormones.
The amount of “free” hormones is much smaller than the amount of “bound” hormones.
This protein binding is one of the ways that the body uses to regulate the hormone levels.
So what about SHBG?
SHBG levels naturally increase as we age. Since most hormone levels naturally decline as well, this makes a deficiency of those hormones (especially testosterone) even more pronounced.
Sex Hormone Binding Globulin binds to several different hormones. The body uses SHBG to inactivate these hormones in the bloodstream.
Too much of it can be bad because it can bind so much of the hormone that we can have symptoms caused by a lack of that hormone.
Too little can also be bad because it can cause an excess of certain hormones which also causes symptoms.
Even small changes in SHBG can cause substantial symptoms and problems.
SHBG has a stronger affinity for some hormones that others.
It will preferentially bind to sex hormones in this order (from highest affinity to lowest):
As you can see, SHBG has a greater affinity for androgens than estrogens.
You can therefore predict the symptoms you may have by knowing the effect that the SHBG level has on your androgen levels.
For example, if you have an elevated SHBG, it will bind DHT and testosterone which will cause symptoms of low testosterone (weight gain, depression, increased belly fat, loss of muscle, etc.).
With low levels of SHBG, you will have more unbound or free testosterone which will cause symptoms of high testosterone (acne, facial hair growth, PCOS, etc).
Hopefully you can see why it’s important to check your SHBG level if you are having any symptoms of hormonal imbalance to help you and your doctor determine what issues are going on in your body.
The optimal range for SHBG is 60-80 nmol/L. Any level below or above this range should be investigated.
There are several things that I will list below that can elevate SHBG levels.
An increase in either or both of these hormones will stimulate the liver to increase SHBG production.
A SHBG level > 80 nmol/L is considered too high.
Another hormone to keep in mind that is closely linked to SHBG is cortisol.
Cortisol is our stress hormone. In times of increased stress (physical or mental), our adrenal glands increase cortisol production.
An elevated cortisol level stimulates the liver to increase SHBG production.
Please realize that an elevated level of SHBG does not in itself cause any symptoms.
The symptoms are caused by the effect that the high SHBG level has on hormones in the body.
Most of the symptoms will be due to either excess estrogen and/or low testosterone:
If the elevated SHBG is caused by the situation of a high thyroid level (hyperthyroidism or excessive oral thyroid medication), you can also have symptoms related to the elevated thyroid such as tremor, palpitations and weight loss.
Treating an elevated SHBG has more to do with finding the cause of the elevation rather than treating the elevated SHBG itself.
There are several things you should consider doing:
The ratio of these 2 hormones is more important than the numbers themselves.
Check the levels in the middle of your cycle (2 weeks after your last period) for the best results.
If the ratio of estrogen:progesterone is >10:1, you have estrogen dominance that needs to be addressed.
If your estrogen level is normal, then it is highly likely that your thyroid is the culprit of your elevated SHBG.
Check a complete thyroid panel, especially free T3 and free T4.
If these are elevated and you are on thyroid medication, you may need to lower your dose or even change your thyroid medication.
If you aren’t on thyroid medication, you need to have more testing done ASAP to find the cause of your elevated thyroid (most likely Grave’s Disease).
I discuss several techniques to better manage your stress in my article on Adrenal Fatigue.
Low SHBG is more difficult to detect and often harder to treat.
As a result, it is often ignored much more than an elevated SHBG.
A low SHBG typically occurs in menopausal women or patients with hypothyroidism (low thyroid).
So if your SHBG is < 60 nmol/L, you should look at estrogen and thyroid as the probable causes if you are menopausal.
If you are still menstruating, then hypothyroidism is the likely cause.
If one or both of those hormones is low, SHBG levels will drop which will increase free testosterone, paving the way for conditions such as PCOS.
This series of hormone imbalances also appears to set up a person to develop insulin resistance.
In fact, a low SHBG level has been shown to be a strong predictor for type 2 diabetes in both men and women.
The symptoms associated with a low SHBG are typically caused by low thyroid hormone, low estrogen, and elevated testosterone. The include:
Keep in mind that your individual symptoms will depend on which hormones are out of balance and to what extent.
If you have a low SHBG, you should consider the following things:
Compare these tests with their optimal levels to determine if you have a thyroid issue.
If your thyroid function is low, it is probably affecting your SHBG level and you will need to consider taking a thyroid medication and doing other things to help boost your thyroid function.
After menopause, your estrogen levels will drop which can drop your SHBG level.
If that is the case in your situation, you might need to consider bioidentical hormone replacement therapy.
If your SHBG level is low, there will be less of it to bind to testosterone, so it may cause your free testosterone level to rise.
This can usually be alleviated by maximizing your thyroid medication which will raise your SHBG level.
One final benefit of checking your SHBG level is it a good indicator of the thyroid function in your body.
In states of low thyroid function, the SHBG level drops.
In states of high thyroid function, the SHBG level rises.
This allows the SHBG to be used as a marker to assess the thyroid hormone absorption and cellular function.
If you have low SHBG and hypothyroidism, you should test your SHBG level at the beginning of treatment to assess if you are on the right type of thyroid hormone and the right amount.
If you are taking a T4 only thyroid medication and your SHBG level does not increase, you may have a problem with peripheral conversion of T4 into active T3.
You therefore may need to change to a natural dessicated thyroid (NDT) or add T3 to your current regimen.
On the flip side, if after starting your thyroid medication your SHBG level rises > 80 nmol/L, that is an indication that your dose is too high and it should be reduced.
The sex hormone binding globulin level gives us important information on the status of several hormones in the body.
A high level is typically caused by estrogen excess and excess cortisol.
A low level is typically caused by low thyroid. It also is an indicator that you may be having issues with insulin resistance.
The key to treating an abnormal SHBG level is to identify what is causing the abnormality and correct it.
Doing this will help return the SHBG level to the optimal range and reduce symptoms.
Now it’s your turn…
Do you have an abnormal SHBG level?
Have you identified the cause or causes?
Please leave your comments below.
Why is testosterone so important?
It may be the most misunderstood of all of the hormones in the body.
Thanks to anabolic steroids and the misuse of them, many people are afraid of testosterone and have received lots of false information about it.
In fact, it is an essential hormone that both men AND women need to live happy, healthy, energetic lives.
If the levels of testosterone are not optimal in your body, it will be almost impossible to have the quality of life that you should ideally have.
If you are having fatigue, loss of muscle strength, loss of libido, night sweats, headaches, cold intolerance, and if you are gaining belly fat, you may have a testosterone problem.
Let’s dive into this hormone further to learn more about it and address much of the misinformation that many people may have. I will also discuss symptoms, testing and treatment.
Testosterone is a hormone that is produced in the testes and to a lesser degree in the adrenal glands in men. It is produced in the ovaries and adrenal glands in women.
Testosterone is the hormone that grows tissue in the body.
It is responsible for muscle growth, bone growth, hair growth, sexual function, sexual drive (libido) and is essential for overall health and feelings of well-being.
Let’s dive into these more.
I believe that optimizing hormones is key for prevention of disease, including heart disease
A study from the American Heart Association’s journal Circulation showed that as the testosterone level drops in men, their risk of heart disease increases.
The authors even suggested that the testosterone level could potentially be used as a marker for predicting which patients were at high risk of developing heart disease.
By the way, doctors today are taught that statin medications (Lipitor, Zocor, etc) are essential to reduce the risk of heart disease.
In fact, if you follow some of the guidelines, the majority of adults should be on a statin.
However, whether statins actually reduce the incidence of heart disease is controversial.
I personally think it is more important to get the body into balance, including hormones. Most inflammation and disease will resolve without the need for medications.
Studies have shown that low testosterone has been associated with worsening cognitive function in older men.
On the flip side, it also appears that testosterone therapy improves mental function in men.
In case you’re wondering, it also seems to help in women.
A study published in 2013 found that low testosterone levels may help predict if a man will develop insulin resistance or type 2 diabetes in the future.
It is unknown whether low testosterone increases the risk of diabetes, or if both conditions are due to the majority of those patients being overweight.
Regardless, there is a definite connection between low testosterone and type 2 diabetes.
Doctors have been taught that testosterone can cause or worsen prostate cancer.
This simply is not true.
This belief was based on a flawed study from 1941.
In one study, healthy males were given super high doses of testosterone, but they had no increase in PSA or the size of their prostate glands.
In fact, having low levels of testosterone was shown to be a risk factor for developing prostate cancer!
1 in 7 of postmenopausal women have osteoporosis.
Half of all women over 50 can expect to suffer an osteoporosis-related fracture during their lifetime.
After a hip or vertebral fracture, death either caused directly from the fracture or due to a secondary problem is as high as 25-35%!
That is why we should do all we can to reduce this risk.
Testosterone has been shown to increase bone density.
By the way, calcium does not increase bone density significantly, but vitamin D reduced the risk of fractures by 16%.
Testosterone also seems to protect against breast cancer.
It is believed that testosterone down-regulates the estrogen receptors in the breast which inhibits breast cancer growth.
Conditions such as PCOS where the testosterone levels are elevated are not associated with higher breast cancer rates. In fact, they may actually have lower rates.
By the way, micronized progesterone does not increase breast cancer and may in fact be protective.
If you are on synthetic progesterone (medroxyprogesterone, norethindrone, etc), you should talk to your doctor about switching to micronized progesterone (Prometrium or bioidentical).
There is also evidence that iodine supplementation reduces breast cancer risk.
If you have 5 or more of the above symptoms, you have a high likelihood of having a low testosterone level and it’s time to go get tested.
Many of the symptoms of testosterone deficiency mirror those caused by other hormone issues, especially hypothyroidism and adrenal fatigue.
Are you tired because you have low thyroid, low testosterone, or adrenal fatigue?
What about your insomnia, or weight gain, or mood swings? Which one is causing it?
The answer is possibly all of them!
That is why you need a thorough history and comprehensive lab tests performed before your individual story becomes clear.
Bonus information for women: If you have hot flashes during the day – 40 seconds of heat that begins in your chest then moves to your face – you most likely have low estrogen levels.
If you have night sweats – you wake up drenched in sweat to the point that you sometimes even have to change clothes – you are most likely low in testosterone.
I believe it is essential to diagnose and treat adrenal and thyroid issues before addressing the sex hormones such as testosterone.
They should at the very least be addressed at the same time.
If your testosterone is low but you are also dealing with adrenal and thyroid issues, you simply won’t feel better until your adrenal and thyroid issues are corrected, even if the testosterone becomes optimized.
So, how do you know if you are low in testosterone?
At this point, I have found insufficient evidence that salivary testosterone measurements are a reliable form of testosterone testing. I therefore recommend serum testing only.
It is important to point out that there is a difference between a “normal” reference range on a lab result and an “optimal” testosterone level.
On most labs, the normal reference range for testosterone in men is about 300 to 1200. That is a HUGE range.
Most insurance plans require 2 different total testosterone levels below 300 before they will pay for testosterone replacement therapy, whether the patient is symptomatic or not.
But people that are having symptoms may benefit even if their testosterone level is as high as in the low 600s.
The optimal range in men should be in the upper 1/3 of that range (I prefer 900-1100).
In women, most labs list a normal reference range of about 15-70 ng/dl.
However, excluding conditions such as PCOS, the optimal range for testosterone in women should be 150-250 ng/dl.
A man qualifies and should be considered for testosterone therapy if:
A woman is a candidate for testosterone therapy if:
Studies have shown that testosterone therapy improves many things, including libido, quality of erections, increased lean mass, increased bone density, improved lipid parameters, reduced fat mass, and improved blood sugar control. Here are 2 examples – here and here.
With that in mind, let’s look at treatment options.
There a 3 types of testosterone therapy available for men – topical, injections, or subcutaneous pellets.
1. Topical – Androgel®, Axiron®, Fortesta®, Testim®, Vogelxo®, transdermal patch-
2. Injections – testosterone cypionate, testosterone undecanoate
3. Subcutaneous Pellets –
There are currently no pharmaceutical testosterone therapies for women.
However, there are still 2 treatment options that can be extremely beneficial:
1. Compounded bioidentical creams
2. Subcutaneous pellets
If she has a history of breast cancer, she could receive testosterone pellets with anastrazole – but no estrogen.
When prescribed correctly, side effects are usually minimal. However, we are talking about a hormone, so it is possible to notice some changes. They may include:
Testosterone is an important hormone in the body and is vital for well-being and energy.
Studies show that it helps prevent heart disease, dementia, osteoporosis, and possibly breast cancer.
When managed closely by an experienced provider, it is a safe and effective therapy for multiple symptoms associated with menopause, andropause, and the aging process.
Now it’s your turn.
Do you think you have low testosterone?
Have you been tested?
Have you ever been treated for low testosterone?
Did testosterone therapy help you?
Leave your comments below!