Testosterone and Men with Thyroid Problems

Testosterone levels are often a problem for men with thyroid problems.

This is no real surprise as all systems of the body are impacted when thyroid hormones are low or are not working effectively.

I will assume in this post that all the basics of low iron, B12, other nutrients, low cortisol and blood sugar issues have been addressed and are not relevant.

There are many connections that men should be aware of:

Low thyroid hormone often results in low testosterone levels.

Low testosterone in men will result in a lowering of D1 activity (one of the deiodinases involved in the conversion of FT4 to FT3).

Low thyroid hormone levels may lead to lower growth hormone levels and this, in turn, may reduce FT4 to FT3 conversion and increase reverse T3 (growth hormone supplementation is known to increase FT4 to FT3 conversion and reduce reverse T3).

Low testosterone often causes significant symptoms. Two of the most common symptoms are depression and low libido. Muscle loss and lower energy levels can also result. You can look up more information on symptoms quite easily on the Internet.

When looking at testosterone levels it is important to test:

  • Total Testosterone.
  • Sex Hormone Binding Globulin (SHBG).
  • Free Testosterone (ideally, although this can be estimated using total testosterone and SHBG).
  • In some cases where aromatisation is a concern, Estradiol should be also be checked.

Free Androgen Index (FAI) is sometimes used to estimate Free Testosterone if all you have is Total Testosterone and SHBG.
FAI = Total Testosterone x 100/SHBG

There are Free and Bio-Available Testosterone Calculators on the Internet. These require Albumin as well as SHBG and Total Testosterone and are more of an accurate estimate of Free Testosterone than the FAI.

Here is a good link to begin your own research with: http://nahypothyroidism.org/deiodinases/

For a man with low cortisol not caused by Addison’s disease, or hypopituitarism, the Circadian T3 Method (CT3M( can be a real blessing.

CT3M can often raise testosterone levels in men. Male thyroid patients have often seen 30% increases in total testosterone levels when using CT3M. I know my own levels came up from the very low end of the reference range to mid-high end of the reference range with CT3M.

Whether you can use the CT3M depends on whether you have low cortisol or not. If you do not, CT3M won’t help you, and in fact, could cause issues by raising cortisol to too high a level. But for those men that need to address low cortisol, CT3M may work well to raise testosterone levels.

Let me briefly discuss sex hormone-binding globulin (SHBG).

In both men and women, SHBG is the protein that carries the sex hormones testosterone and oestrogen. Only the testosterone and oestrogen that is not bound to SHBG (and some albumin – but I’m not going into that in this post) is biologically active.

If testosterone levels stay the same and SHBG rises, there is less biologically active testosterone and a guy can not feel well. So, when a man (or a woman) has testosterone checked, they should also have SHBG checked at the same time.

For those thyroid patients who have to use T3 replacement, this sometimes may drive SHBG up. Multi-dosing using the dosage management process in the Recovering with T3 book helps because the process arrives at an effective T3 dosage with low individual T3 doses and low total levels of T3.

If SHBG is still an issue then there are multiple approaches.

Some patients have said that the use of milk thistle can sometimes bring SHBG down. Stinging nettle root extract (it has to be the root) in capsules can really help to lower SHBG. Stinging nettle root comes in 250 mg and 500 mg capsules and the dosing typically is done 2-3 times per day over the day.

There is also a drug called Danazol that can be used in low doses as an off-label approach to reducing SHBG (100 mg every other day is typical).

Danazol supposedly cuts SHBG in half within 6-8 weeks.

Note: Danazol is a prescription drug and its use to reduce SHBG is an ‘off label’ application. Danazol should only be considered under the supervision of a knowledgeable physician.

Some doctors prefer to provide transdermal, or injected testosterone to a high enough level to overcome any SHBG, as testosterone will ultimately suppress SHBG, although this can lead to other problems e.g. higher estrogen levels (aromatisation).

If low testosterone is an issue, it should be discussed with a knowledgeable doctor or specialist.

I hope this was useful.

Best wishes,


Paul Robinson

Paul Robinson is a British author and thyroid patient advocate. The focus of his books and work is on helping patients recover from hypothyroidism. Paul has accumulated a wealth of knowledge on thyroid and adrenal dysfunction and their treatment. His three books cover all of this.

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  1. Brian on 2nd August 2020 at 10:19 am

    Hello my friend. I am in the midst of trying to figure out my Thyroid issues. I have been dealing with some real deal Thyroid symptoms. Fatigue, dry hair, hair loss, dry skin, weak muscles, easy muscle fatigue, muscle spasms, even nerve issues. My RT3 is high at 533 pmol/L and my FT3 is at the high end of normal. Recently I got my Hormones checked and my Testosterone levels were cut in half from what they were in Jan / Feb. Currently test is at 7.7 nmol/L and it was 15.7. Have you seen anything like this before? Thank you for your time


    • Paul Robinson on 2nd August 2020 at 10:38 am

      Hi Brian, I don’t use this website to go into intricate individual details but I will say that high FT3 does not mean the T3 is actually active within the cells. The reason for this is that high reverse T3 is a marker that means the level of D3 deiodinase enzymes (which convert FT4 to rT3), is high. D3 enzymes provide a barrier between the FT3 and the thyroid receptors. So much of your FT3 is blocked.

      It is common to have other hormone levels failing when this happens. These might also include cortisol as cortisol and testosterone both result from pituitary control signals. The pituitary gland runs on T3 and if it too is struggling due to D3 enzymes you can end up with hypothyroidism symptoms and other end hormones that are low.

      The current thyroid treatment is probably not right for you and I don’t mean just some dosage change. I would also get cortisol tested with both a 4 point saliva test and an 8:00am morning cortisol test.

      Good luck!


  2. martin ackbar on 20th September 2020 at 1:07 am

    Very informative

    • Paul Robinson on 20th September 2020 at 9:54 am

      Thank you for your comment.
      Best wishes, Paul

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