What is a good testosterone level and what should I do if it is low?

Testosterone can be measured in 2 ways, Total testosterone (TT) and Free testosterone (FT).

Although there is no clear cut off to what exactly constitutes low testosterone, its widely accepted that total testosterone <12nmol/L would benefit from treatment. (1)

If the TT levels are normal but there are symptoms of TDS (testosterone deficiency syndrome), FT can be measured and FT <250 pmol/L is considered low.

Symptoms of low testosterone can include but are not limited to:

1. erectile dysfunction

2. reduced libido (sexual desire)

3. increase in fat, reduced muscle mass

4. fatigue

5. depressed mood

6. impaired cognitive function

Prevalence of testosterone deficiency in Singapore is 25% or 1 in 4 (2)

There are some medical conditions in which low testosterone levels are more prevalent, such as diabetes and obesity.

Depending on the patient's age, looking out of contraindications for treatment and considering the possible side effects, patients suffering from symptoms of low testosterone can consider Testosterone replacement therapy (TRT).

TRT can be in the form of pills, Gels (Androgel) or intramuscular injections (Nebido) , each with their own set of pros and cons. The aim of TRT is to improve symptoms and not just to attain a "good level". We aim to correct the TT till it reaches the 3rd quartile of the normal physiological range or 15-20 nmol/L. Effects of treatment can been seen in as fast as 1 month depending on the type of symptoms experienced.

Hope this gives you some clarity, please seek help if you have more queries.

Regards
Dr Mark Lim

References

1. SMHS Testosterone Deficiency Syndrome Guideline.

2. Morgentaler A, Zitzmann M, Traish AM, Fox AW, Jones TH, Maggi M, Arver S, Aversa A, Chan JC, Dobs AS, Hackett GI, Hellstrom WJ, Lim P, Lunenfeld B, Mskhalaya G, Schulman CC, Torres LO. Fundamental Concepts Regarding Testosterone Deficiency and Treatment: International Expert Consensus Resolutions. Mayo Clin Proc. 2016 Jul;91(7):881-96. doi: 10.1016/j.mayocp.2016.04.007. Epub 2016 Jun 21. PMID: 27313122.

Testosterone levels are usually higher in the morning, so the blood test should be performed before 10:00 a.m. in younger men.

For men over 45, the test can be performed until 2:00 p.m. and still receive accurate results.

When you receive the blood test results, the normal range of tesoterone levels will be indicated on the form. In general, the normal range in males is about 270-1070 ng/dL with an average level of 679 ng/dL.

A normal male testosterone level peaks at about age 20, and then it slowly declines. Testosterone levels above or below the normal range are considered by many to be out of balance. Moreover, some researchers suggest that the healthiest men have testosterone levels between 400-600 ng/dL.

Most of the testosterone that circulates in the bloodstream is bound to a special carrier protein called sex hormone binding globulin (SHBG). The more SHBG there is, the less free, active, bioavailable testosterone is able to get out of the blood into the cells to do its job. As we age, testosterone drops and SHBG increases. Although total testosterone may drop only slightly up to age 70, free testosterone drops more rapidly.

Many men with low testosterone do end up seeing many specialists from different fields as the manifestations of androgen deficiency can be seen in many areas of the body. They commonly manifest the following symptoms or conditions:

• low energy level
• fatigue and mental fogginess
• irritability
• anxiety
• decreased muscle mass
• infertility
• problems with erection
• low libido and sexual interest
• hair loss
• loss of bone mass
• breast swelling (gynecomastia)

If there is a sudden drop in testosterone levels, the causes would include the following:

• physical injury to the testicles.
• mumps infection affecting the testicles.
• cancer treatments – chemotherapy and radiation can affect the testicles.
• pituitary disorders caused by medications, kidney failure or tumours.
• obesity – as high body fat can affect the production of male hormones.
• medications like opioid pain medicines and steroids - they can affect the function of pituitary gland and hypothalamus.

At the clinic, it is sometimes challenging to tell if the patient has low testosterone or is suffering from depression. People who have depression but have normal hormone levels generally do not experience breast swelling and decreased muscle mass and strength that are associated with low testosterone.

A blood test may help. For many patients, both depression and low testosterone level need to be monitored and treated.

Male hypogonadism usually is treated with testosterone replacement to return testosterone levels to normal. Testosterone can help counter the signs and symptoms of male hypogonadism, such as decreased sexual desire, decreased energy, decreased facial and body hair, and loss of muscle mass and bone density.

Unpleasant side effects were minimal, and limited to mild gastric irritation in some patients who took the tablet form. Blood pressures were unchanged or even fell slightly in the treatment group after six months. There were no adverse changes in blood fat patterns, glucose or liver function test.

However, for older men who have low testosterone and signs and symptoms of hypogonadism due to ageing, the benefits of testosterone replacement are less clear.

If there is any indication of possible prostate cancer, testosterone should not be prescribed. Nor should it be prescribed for men who have breast cancer. If a man has sleep apnea, this condition should be treated before testosterone therapy is considered.

Another vital point is that it is important to maintain a healthy lifestyle. Testosterone replacement therapy is not a magic cure for years of unhealthy living.