What Are Normal Testosterone Levels in Men?

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As a society, we tend to place a lot of significance on certain words. The word “normal” is one of them. With that in mind, one of the most often asked questions in the field of men’s health is “what are normal testosterone levels in men?” Both the media and health professionals are capitalizing on this question by talking about “low T” and urging men to turn to hormone replacement therapy to boost their testosterone levels.

But before men should even consider taking steps to raise their testosterone levels (which can be done in a number of natural ways), we return to the basic question: what are normal testosterone levels in men? Here is the not-so-simple answer.

 

What are the forms of testosterone?

First of all, there is more than one form of testosterone:

  • One is bonded with sex hormone binding globulin (SHBG), which is the most common type and makes up about 65 percent of total testosterone. The testosterone attached to SHBG typically cannot be separated from the hormone, so this T is not considered to be bioavailable. Testosterone that is bioavailable is the form that is used by the body.
  • One is bonded to the protein albumin, making up about 35 percent of your total testosterone. This testosterone is considered to be potentially bioavailable because it can be “coaxed” away from the protein.
  • One is free, which means it is not attached to any protein. Free testosterone makes up about 2 percent of total T and is the form that is completely bioavailable to be used by the body. Free testosterone travels throughout the bloodstream and can bind to receptors in the muscles, brain, and other organs.

Getting your testosterone levels checked

After you undergo the simple blood test that measures your testosterone levels, your doctor will give you the results represented by three different numbers:

  • Total testosterone. This represents the total amount of testosterone that is circulating throughout your body, so it includes both types of bonded T plus free T
  • Bioavailable T, which consists of testosterone attached to albumin plus free T
  • Free T

Now comes the complicated part. The definition of “normal” testosterone varies, depending on the expert and the testing lab used. The good news is that there are general guidelines for “normal” testosterone. Here are the generally accepted normal ranges of total, free, and bioavailable T, given in nanograms of testosterone per deciliter (ng/dL) for different age groups:

Total T:

  • 240 to 950 ng/dL for men age 19 years and older

Free T:

  • 5.05 to 19.8 ng/dL for men 25 to 29
  • 4.86 to 19.0 ng/dL for ages 30 to 34
  • 4.65 to 18.1 ng/dL for ages 35 to 39
  • 4.46 to 17.1 ng/dL for ages 40 to 44
  • 4.28 to 16.4 ng/dL for ages 45 to 49
  • 4.06 to 15.6 ng/dL for ages 50 to 54
  • 3.87 to 14.7 ng/dL for ages 55 to 59
  • 3.67 to 13.0 ng/dL for ages 60 to 64
  • 3.47 to 13.0 ng/dL for ages 65 to 69
  • 3.28 to 12.2 ng/dL for ages 70 to 74

Bioavailable T:

  • 83 to 257 ng/dL for men 20 to 29
  • 72 to 235 ng/dL for men 30 to 39
  • 61 to 213 ng/dL for men 40 to 49
  • 50 to 190 ng/dL for men 50 to 59
  • 40 to 168 ng/dL for men 60 to 69

No ranges have been determined for men age 70 and older. Clinically low total testosterone levels are recognized as less than 220 to 300 ng/dL.

Bottom line on normal testosterone levels in men

Here is the bottom line when it comes to answering the question, what are normal testosterone levels in men.

  • The range of “normal” is wide, which accommodates the fact that every man’s needs are different.
  • While men’s total testosterone level can be within the normal range, their free T levels can be low, which can result in symptoms of low T.
  • The testosterone level men should be most interested is in the bioavailable number. If men can boost their bioavailable testosterone level, they should expect an increase in energy, sex drive, and muscle strength as well as better mood and well-being.

Article Source: https://www.huffingtonpost.com/entry/what-are-normal-testosterone-levels-in-men_us_5968d687e4b06a2c8edb45e9

Written By: Craig Cooper

“The Greatest Health of Your Life”℠

Boston Testosterone Partners
National Testosterone Restoration for Men
Wellness & Preventative Medicine

Total Testosterone vs. Bioavailable Testosterone: Why SHBG Matters

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Sex Hormone Binding Globulin or SHBG is essential to maximizing the availability of testosterone, the substance every man wants to measure. Today, science is telling us that both men and women need an optimized hormonal profile, and testosterone is widely known to be important for men.

Why SHBG is Important for Your Health and Performance

Sex hormone binding globulin (SHBG) is a glycoprotein primarily produced in the liver and most commonly found in the bloodstream. It binds to any of 17 sex hormones, including testosterone and estrogen, and transports these chemicals throughout the body. Testosterone and sex hormones are referred to as “bound” when attached to SHBG. When these hormones are not bound to SHBG, they are referred to as “free”, or “bioavailable”, and can freely exert their effects upon your body. The sum of bound and free testosterone is referred to as total testosterone.

It is well-known that a proper balance of testosterone and other sex hormones have a crucial impact on your health. Excessively high SHBG is problematic especially for males and athletes because it decreases the amount of free testosterone. High levels of SHBG are associated with infertility, a decreased sex drive, and erectile dysfunction, especially when total testosterone levels are already low. In both men and women, low levels of free testosterone can result in reduced muscle growth and impaired post-workout recovery. Additionally, recent research suggests that high levels of SHBG bind to estrogen and reduce bone mass in both men and women- potentially leading to osteoporosis. Thus, optimal SHBG levels are crucial in maintaining proper bone health and some experts are now suggesting routine measurement of SHBG as a useful new marker for predicting severe bone diseases.

So how do you know if you need to increase or decrease your SHBG levels? The only way is to get your blood tested. Once you know your SHBG levels, you can make the proper lifestyle changes to modify your levels and optimize your health

By: Heather Schwartzmann, PA-C

“The Greatest Health of Your Life”℠

Boston Testosterone Partners
National Testosterone Restoration for Men
Wellness & Preventative Medicine

 

More magnesium, more free testosterone

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Men with more magnesium in their blood are likely to have a higher amount of free testosterone in their body. Chemical analysts draw this conclusion in an article published in the Journal of Pharmaceutical and Biomedical Analysis.

About sixty percent of the body’s testosterone is attached to sex hormone binding globulin (SHBG) [spatial structure above]. Androgens bound to SHBG lose their anabolic effect but probably retain their androgenic effect. In the prostate, for example, there are SHBG receptors and they send error signs to the prostate cells if they attach themselves to SHBG with androgens bound to it. Androgen steroid hormones incorporated by SHBG therefore do have undesired effects, but no desirable effects.About two percent of the testosterone in the body is active: it is not attached to binding proteins which prevent testosterone from interacting with its receptor. About forty percent of the body’s testosterone is attached to albumin, a protein that can let go of the hormone. Free testosterone and testosterone attached to albumin are referred to as bio-available testosterone.

As men get older, SHBG sweeps up more and more testosterone. This is also because older men eat less protein. Low protein consumption raises the concentration of SHBG in the blood. A higher protein intake results in more albumin, and that increases the amount of bio-available testosterone. Within limits, of course.

The researchers, linked to the Université de Franche-Comté, extracted SHBG from the blood of young men, and exposed the protein to magnesium ions. Then they measured how fast the testosterone attached itself to SHBG at increasing magnesium concentrations. The higher the magnesium concentration, the lower the attraction.

Although the researchers did not examine whether more magnesium actually leads to more free testosterone in humans, they believe their findings are meaningful at the physiological level.

“The results presented here provide evidence for an Mg2+-mediated variation of the testosterone-SHBG association, suggesting that an increase of the Mg2+-concentration inside the biological concentration range (0.75mM-1.0mM) could lead an enhancement of the bioavailable testosterone”, they write.

Fifteen years ago researchers examined the effect of extremely high – and biologically improbable – magnesium concentrations. These led to a small decline in the testosterone level. [Horm Metab Res. 1993 Jan;25(1):29-33.]

The researchers have announced that they will soon be publishing their findings on the effect of plant substances on the binding of testosterone to SHBG.

Magnesium in food is found in plant products. Good sources are fibre-rich breakfast cereals, spinach, nuts and beans.

Sources:
Journal of Pharmaceutical and Biomedical Analysis, doi:10.1016/j.jpba.2008.10.041

Article Source: http://www.ergo-log.com/magnesiumtest.html

“The Greatest Health of Your Life”℠
Boston Testosterone Partners
National Testosterone Restoration for Men
Wellness & Preventative Medicine