Testosterone Testing Has Improved. One Test Still Isn’t Enough.

If you have wondered whether testosterone care is better today than it was a decade ago, the answer is yes, but only when it is done correctly.

Laboratory methods have improved. Clinicians have better safety data. Professional guidelines have become more consistent about how testosterone deficiency should be diagnosed. We also understand more about the many factors that can temporarily lower a man’s testosterone.

At the same time, testosterone has become a heavily marketed product. Men are often encouraged to connect fatigue, weight gain, poor sleep, low motivation, or brain fog directly to “low T.” Those concerns are real, but they are not specific to testosterone deficiency. Testing should help identify the cause of a problem, not just be a step before starting a treatment.

The principle is simple: test, don’t guess. And make sure the testing is done properly.

Testosterone testing is more reliable than it used to be

One of the biggest improvements has occurred inside the laboratory.

Historically, the same blood sample could produce considerably different testosterone results depending on which laboratory or testing method was used. Standardization programs, including the CDC’s Hormone Standardization Program for Testosterone, have helped improve the consistency of participating assays.

More laboratories also have access to liquid chromatography-tandem mass spectrometry, commonly called LC-MS/MS. This method can provide greater accuracy and specificity, particularly when testosterone concentrations are very low.

However, the name of the technology does not guarantee a perfect result. Laboratories, testing platforms, reference ranges, sample quality, and timing still matter. The Endocrine Society continues to emphasize the use of accurate, standardized assays because nonstandardized testing can produce meaningfully different results from the same sample.

Better testing exists. That does not mean every testosterone test is equally reliable.

A single low result is not a diagnosis

Testosterone naturally fluctuates. It can be affected by the time of day, food intake, sleep, acute illness, calorie restriction, certain medications, and recent physical stress.

That is why reputable guidelines generally require more than one result. A responsible evaluation normally includes:

• Symptoms or physical findings consistent with testosterone deficiency
• At least two low testosterone measurements taken on separate mornings
• Testing performed with an accurate laboratory method
• Additional evaluation to determine why testosterone is low

The American Urological Association uses total testosterone below 300 ng/dL as a reasonable diagnostic threshold, while other organizations use somewhat different cutoffs. The number should not be viewed in isolation. A laboratory result becomes clinically meaningful when it is interpreted alongside symptoms, health history, medications, physical findings, and repeat testing.

The Endocrine Society recommends diagnosing hypogonadism only when a man has both consistent symptoms and unequivocally, repeatedly low testosterone levels. It also recommends confirming the result with another fasting morning measurement.

In other words, a low number deserves investigation, not an automatic prescription.

How you prepare for the test matters

For most men, testosterone should be measured early in the morning, commonly between 7:00 and 10:00 a.m., when concentrations are generally highest. Whenever possible, testing should also occur:

• After a normal night of sleep
• While fasting
• When you are not acutely ill
• Without unusually severe training or calorie restriction immediately beforehand
• After reviewing medications that could suppress testosterone with the clinician

Opioids, glucocorticoids and certain other medications can affect testosterone production. Poor sleep and sleep disorders may also influence hormone levels. Testing under abnormal conditions can make a temporary change look like a chronic medical problem.

If the first result is low, repeating the test under appropriate conditions helps determine whether the finding is persistent.

Total testosterone may only be the beginning

Total testosterone is typically the starting point, but it is not always the complete answer.

Most testosterone in the bloodstream is attached to proteins, including sex hormone-binding globulin, or SHBG. Changes in SHBG can make total testosterone appear lower or higher without accurately reflecting the testosterone available to tissues.

Obesity, diabetes, thyroid disorders, liver disease, aging, and certain medications can affect SHBG. When total testosterone is borderline or an SHBG abnormality is suspected, a clinician may consider SHBG, albumin, and calculated free testosterone.

Additional testing may include:

• Luteinizing hormone and follicle-stimulating hormone, to help identify whether the problem originates primarily in the testes or in the signaling system involving the pituitary and hypothalamus
• Prolactin when secondary hypogonadism is suspected
• Thyroid testing when symptoms or history indicate it
• Iron studies or pituitary evaluation in selected patients
• Hematocrit before testosterone therapy
• PSA and prostate-risk evaluation when appropriate for the patient’s age and risk factors

Not every man needs every test. The purpose is to investigate the likely cause rather than order the largest possible hormone panel.

Sometimes low testosterone is a signal, not the primary problem

One of the most important advances in men’s health is a better understanding of functional or potentially reversible testosterone suppression. Testosterone can be reduced by:

• Obesity
• Poorly controlled diabetes
• Sleep apnea
• Acute or chronic illness
• Opioid or glucocorticoid use
• Severe calorie restriction
• Excessive training without adequate recovery
• Certain pituitary or hormonal disorders

In some men with obesity, total testosterone is low partly because SHBG is low, while free testosterone may remain within an expected range. In that situation, looking only at total testosterone could lead to an incomplete or incorrect conclusion.

Treating sleep apnea, losing excess weight, improving metabolic health, reviewing medications, eating adequately, and allowing appropriate recovery may improve testosterone while also addressing the underlying health issue.

That does not mean every low result can be corrected through lifestyle. It means a good evaluation asks why testosterone is low before deciding what to do about it.

Our understanding of testosterone therapy is better, but not complete

The evidence surrounding testosterone therapy has also become clearer.

The large TRAVERSE trial studied more than 5,000 middle-aged and older men with symptoms, repeatedly low testosterone, and existing cardiovascular disease or elevated cardiovascular risk. Testosterone therapy was not associated with a higher rate of major cardiovascular events than placebo during the study period.

Those findings contributed to the FDA’s 2025 decision to remove language about an increased risk of adverse cardiovascular outcomes from the boxed warning for testosterone products. The FDA also required warnings regarding increased blood pressure.

That is reassuring, but it should not be interpreted as meaning testosterone is risk-free. In TRAVERSE, pulmonary embolism, atrial fibrillation, certain arrhythmias, and acute kidney injury occurred more frequently in the testosterone group. The trial also does not settle every question about very long-term use or every type of patient.

Testosterone can also raise hematocrit, suppress sperm production, affect fertility, increase PSA, and create formulation-specific adverse effects. These are reasons for careful selection and monitoring, not reasons to avoid appropriate treatment in every man.

Treatment should match the man’s goals

Fertility is particularly important.

Exogenous testosterone can suppress the hormonal signals needed for sperm production. A man who wants to preserve or restore fertility should discuss that goal before beginning therapy. Depending on the diagnosis, a qualified clinician may consider different approaches rather than automatically prescribing testosterone.

Monitoring should also be established before treatment begins. Depending on the patient and therapy, that may include symptoms, testosterone levels, hematocrit, blood pressure, PSA, prostate risk, side effects, fertility goals, and whether treatment is providing a meaningful benefit.

Responsible care goes beyond a prescription. It means making the right diagnosis, selecting an appropriate option, and continuing to evaluate the result.

What should you ask before beginning testosterone therapy?

Before accepting a diagnosis or starting treatment, consider asking:

• Was my testosterone tested early in the morning?
• Was the low result confirmed on a separate day?
• Do my symptoms reasonably fit testosterone deficiency?
• What laboratory method and reference range were used?
• Should SHBG or calculated free testosterone be evaluated?
• Were LH and FSH checked to help identify the cause?
• Could sleep, weight, illness, medication, nutrition, or training be affecting the result?
• How could treatment affect my fertility?
• What are the realistic benefits for my particular symptoms?
• What is the plan for monitoring effectiveness and safety?

A quality provider should be comfortable answering those questions.

The bottom line

Men have access to better testosterone testing and stronger clinical evidence than they did a decade ago. We are better able to identify genuine testosterone deficiency, investigate its cause, understand the benefits and limitations of treatment, and monitor therapy responsibly.

But improved science does not automatically produce improved care.

The best care still begins with the basics: listen to the man, evaluate his symptoms, obtain reliable testing under the right conditions, confirm the result, investigate the cause, discuss fertility and safety, and then make an informed decision together.

Your health deserves real numbers, careful interpretation, and a plan built around you.