Medically reviewed by Dr Todd On, Associate Consultant, Family Physician, MBBS, GDFM, MMED (FM), MCFP (S)
Key takeaways
- Low testosterone (hypogonadism) is a medical diagnosis that needs both symptoms and consistently low blood tests. Neither alone is enough.
- Symptoms such as low energy, low drive and low mood are common in men and have many causes, so they should be evaluated properly, and not be assumed to be hormonal.
- A proper assessment uses at least two early-morning tests, ideally from a laboratory with a standardized assay.
- Obesity and type 2 diabetes are strongly linked with low testosterone, and for many overweight men, weight loss is the first treatment to try.
- Testosterone therapy has clear benefits for men with a true, diagnosed cause, but it carries risks that require monitoring.
Men’s health conversations often focus on cancer screening, and rightly so. But many men in their forties and beyond also wonder about a different question: is my fatigue, low sex drive or changing body a hormone problem? This article explains how testosterone assessment is meant to work, who benefits from it, and why a rushed test or a quick prescription is not the answer.
What is low testosterone, and how is it diagnosed in men?
The medical term is male hypogonadism. The Endocrine Society states that diagnosis requires two things together: symptoms consistent with low testosterone, plus consistently low, accurately measured blood levels of total and free testosterone. The definition is the same for a man of any age.
Their guidance is to measure fasting early morning total testosterone with an accurate and reliable assay as the first test, then repeat it to confirm. It is recommended to measure it while fasted, as eating can lower testosterone levels. It is also recommended to measure in the early morning, as testosterone levels in men follow a circadian rhythm, naturally peaking in the early morning. Repeating also matters: the guidance notes that about 30% of men whose first result was in the low range have a normal result when repeated.
Recommended Reading: What is Testosterone?
What are the symptoms of low testosterone in men?
Symptoms linked with low testosterone include:
- Reduced sex drive (libido)
- Erectile dysfunction
- Reduced early morning erections
- Reduced muscle mass and strength
- Increased body fat
- Low bone mass
- Depressed mood
- Fatigue
- Low energy
However, these symptoms alone are not diagnostic. Low energy, libido and mood for example, are common in aging men for many reasons, and reversible contributors such as obesity and medications can be contributors.
Who should be tested, and who should not?
In practice, an assessment makes sense for a man who:
- has experienced symptoms that affect his quality of life, particularly sexual dysfunction,
- has been checked for other explanations first, such as weight, medications and other medical conditions.
Although it is not a routine part of a general health screen for a man who feels well, Men’s Health & Testosterone Assessment helps in understanding whether your hormones could be contributing to fatigue, low libido or changes in body composition.
What is the link with weight and diabetes?
Research shows that men with obesity, metabolic syndrome and type 2 diabetes tend to have low total and free testosterone and low levels of sex hormone-binding globulin (SHBG)]. Low total testosterone and low SHBG are associated with type 2 diabetes independent of age and obesity, and low testosterone is common in men with type 2 diabetes, many of whom have symptoms. Obesity is one of the strongest correlates.
The practical consequence is that for low testosterone levels in men due to being overweight or obese with no other identified cause, weight loss is typically the first-line therapy. For men who fit this picture, a baseline health assessment is often the start of a metabolic health conversation rather than a prescription.
What should a proper assessment include?
- A conversation about symptoms and their timeline, including sexual function, mood, energy and sleep.
- A review of reversible contributors, including weight, long-term medicines.
- Two early-morning, testosterone tests at a laboratory using a standardized assay.
- If testosterone is confirmed low, a search for the cause..
- Before any treatment, a discussion of benefits, risks and monitoring.
What should men do next?
- If you feel well: you do not need a testosterone test. Do book the screening that is recommended for your age: cardiovascular and diabetes risk checks from 40, and colorectal screening from 50.
- If you have persistent symptoms: see your doctor, and expect questions about weight, medicines, sleep and mood before any hormone test.
- If you are offered a test or treatment: ask which laboratory and assay will be used, whether the test will be repeated in the early morning, and what monitoring will follow.
- If you are overweight: know that weight loss can improve testosterone levels and metabolic health together, and is often the first step.
If you would like to understand whether hormones could be contributing to fatigue, low libido or changes in body composition, take a look at Men’s Health & Testosterone Assessment. This assessment looks beyond total testosterone by also measuring SHBG, free androgen index, DHEA-S, reproductive hormones and thyroid hormones.
The additional markers help your doctor interpret how much testosterone may be biologically available and whether other hormonal pathways could be contributing to your symptoms.
Tests included are: Testosterone, DHEA-S, IGF-1, SHBG, free androgen index, FSH, LH, prolactin, oestradiol, FT4 and TSH.
About Dr. Todd On
Dr. Todd On, an Associate Consultant and Family Physician with 16 years of experience in tertiary and community care, specializes in person-centered treatment for acute and chronic conditions. He has led quality initiatives in smoking cessation and diabetic care and is an award-winning clinical tutor at the College of Family Physicians Singapore.