What Causes Low Testosterone? Understanding the Root Factors
The short version:
- Low testosterone always has a cause — doctors sort them into primary (the testes themselves) and secondary (the brain’s signaling system).
- The biggest everyday drivers are age, obesity, type 2 diabetes, poor sleep, chronic stress, heavy alcohol use, and certain medications.
- Some causes are reversible — weight loss, better sleep, and a medication change can each restore levels. Others (testicular damage, genetic conditions) usually need ongoing therapy.
- Finding your cause matters, because it determines the right treatment path.
Low testosterone doesn’t just happen. It’s always caused by something — sometimes one factor, often a combination. Understanding what’s driving your deficiency is crucial because it determines your treatment path: hormone replacement therapy, lifestyle changes, treating an underlying condition, or a mix of all three.
Here’s the reality: testosterone deficiency rarely has one obvious cause. It’s usually the result of your hormonal system being affected by age, health conditions, medications, stress, or lifestyle habits. The good news is that once you identify the cause, you have options.
Primary vs. Secondary Hypogonadism
The difference is where the problem sits: primary hypogonadism is a problem in the testes themselves, while secondary hypogonadism is a problem in the brain centers that tell the testes what to do. Doctors — including the American Urological Association’s testosterone deficiency guideline — use this split as the first step in tracking down a cause.
Primary hypogonadism (also called testicular hypogonadism) means the testes — or ovaries, in women — aren’t producing enough testosterone even though the brain is asking for it. The factory itself has the problem.
Secondary hypogonadism (also called central hypogonadism) means the pituitary gland or hypothalamus — the “control centers” in the brain — aren’t sending the production signal properly. The factory is fine; the messaging system is broken.
| Primary Hypogonadism | Secondary Hypogonadism |
|---|---|
| Problem is in the testes/ovaries (the gland itself) | Problem is in the pituitary or hypothalamus (the brain’s signal) |
| Examples: testicular injury or surgery, genetic conditions, chemotherapy or radiation damage | Examples: pituitary tumors, obesity disrupting hormonal signaling, chronic opioid use, excessive endurance training |
| Signal hormones (LH/FSH) are typically high — the brain is shouting at a gland that can’t respond | Signal hormones are typically low or normal — the brain isn’t asking loudly enough |
| More often permanent; usually managed with testosterone therapy | More often has a treatable driver — fixing the underlying cause can restore levels |
In practice, many cases involve both components. What matters most is identifying your specific cause so treatment can be targeted appropriately.
Age: The Slow, Predictable Decline
Testosterone naturally falls roughly 1% per year starting around age 30, making age the most universal contributor. This is normal physiology, not a disease.
However, the rate of decline varies enormously. Some men maintain robust testosterone into their 80s, while others develop significant deficiency in their 50s. The difference often comes down to overall health, lifestyle, and genetics.
Why does this matter? While age-related decline is universal, the need for treatment depends on how far your levels drop and how much it affects your quality of life. A man at 280 ng/dL at age 55 might benefit meaningfully from treatment, while another man at a similar level feels fine. It’s individualized.
Medical Conditions That Lower Testosterone
Obesity, type 2 diabetes, pituitary disorders, testicular conditions, and chronic kidney or liver disease are the most common medical culprits. Sometimes treating the underlying condition restores testosterone on its own; other times replacement therapy is needed alongside it. The Cleveland Clinic’s overview of male hypogonadism lists the same core conditions.
Obesity
Obesity is one of the strongest predictors of low testosterone in men. Excess body fat converts testosterone into estrogen, which suppresses further production, and the insulin resistance that often comes with obesity disrupts hormonal balance further.
The relationship runs both ways: low testosterone makes it harder to keep muscle and easier to gain fat, creating a self-reinforcing loop. Weight loss alone can often raise testosterone significantly, especially when obesity is the primary cause.
Type 2 Diabetes
Diabetes damages blood vessels and nerves, can disrupt pituitary function, and often travels with obesity. Men with diabetes are substantially more likely to have low testosterone than men without it. Better diabetes control can help improve levels, though treatment may still be necessary.
Pituitary Disorders
The pituitary gland controls testosterone production by releasing luteinizing hormone (LH) — the chemical “go” signal to the testes. Pituitary tumors, even benign ones, can disrupt this signaling, as can pituitary surgery, radiation, inflammation, or genetic conditions. These cases often need specialist care.
Testicular Injury or Conditions
Injury to the testes — from trauma, surgery, or accident — can permanently reduce testosterone production. Conditions like varicocele (enlarged veins in the scrotum) or testicular atrophy can do the same. Some of these are treatable; others require long-term hormone replacement.
Chronic Kidney or Liver Disease
Both disrupt the body’s ability to produce and process hormones. Kidney disease increases inflammation and hormonal dysregulation, while liver disease impairs the metabolism of sex hormones. Managing the underlying condition is essential, though testosterone replacement may be needed as well.
Lifestyle Factors That Lower Testosterone
Chronic stress, poor sleep, heavy alcohol use, and inactivity are the four big lifestyle suppressors — and unlike your age, every one of them is within your control.
Chronic Stress and Cortisol
When you’re chronically stressed, your body prioritizes cortisol (the stress hormone). Cortisol and testosterone sit on a seesaw — when one goes up, the other tends to go down — and prolonged stress also blunts the pituitary’s production signal. Stress management through exercise, sleep, and lifestyle adjustments can meaningfully improve levels.
Poor Sleep
Testosterone is produced primarily during sleep, especially deep sleep. When you’re sleep-deprived — from insomnia, sleep apnea (repeated pauses in breathing during sleep), or bad habits — production suffers. Many men are surprised to learn that fixing sleep alone raises testosterone; aim for 7–9 hours of consistent, quality sleep.
Excessive Alcohol
Alcohol directly suppresses testosterone production and raises cortisol. Heavy or frequent drinking is associated with significantly lower levels, and even moderate drinkers sometimes see improvement after cutting back.
Sedentary Lifestyle
Physical inactivity is linked to low testosterone, while regular exercise — especially resistance training — supports it. You don’t need to become a bodybuilder; consistent strength training a few times per week makes a meaningful difference, particularly when combined with weight loss.
Medications That Can Lower Testosterone
Opioids and long-term corticosteroids are the biggest offenders, and several other common drug classes can contribute. If your symptoms began around the time you started a new prescription, that timing is a clue worth raising with your doctor — never stop or adjust a medication on your own.
Common testosterone-suppressing medications include:
| Medication type | Why it lowers testosterone |
|---|---|
| Opioids | Used for pain management; chronic opioid users frequently have very low testosterone |
| Corticosteroids | Drugs like prednisone suppress testosterone significantly with long-term use |
| Some antidepressants | Can suppress testosterone in some individuals — particularly SSRIs |
| Anticonvulsants | Prescribed for seizures or nerve pain; can contribute to lower levels |
| Certain blood pressure medications | Some beta-blockers and other antihypertensives can contribute |
| H2 blockers and proton pump inhibitors | Acid-reflux drugs that can suppress testosterone in some cases |
Sometimes alternatives exist, or a dose adjustment helps. Don’t self-adjust — but do ask the question.
Causes of Low Testosterone in Women
In women, the most common causes are menopause, ovary removal, adrenal problems, and certain medications. Women produce much less testosterone than men, but still need adequate levels for sexual health, muscle, bone strength, and mood.
Menopause and surgical menopause: as estrogen and progesterone fall during menopause, testosterone often drops too. Surgical removal of the ovaries causes an even sharper decline.
Adrenal insufficiency: the adrenal glands (small hormone-producing glands above the kidneys) make part of a woman’s testosterone, so conditions affecting them lower production.
PCOS (polycystic ovary syndrome): interestingly, PCOS typically causes elevated testosterone, but some women with PCOS develop hormonal imbalances that eventually suppress it.
Hysterectomy: even without ovary removal, a hysterectomy can affect hormone production and circulation.
Medications: certain birth control formulations, antidepressants, and thyroid medications can affect testosterone levels.
Reversible vs. Permanent Causes
This is the most practical question of all, because it decides whether you need a temporary fix or ongoing therapy. Roughly speaking, causes fall into two buckets:
| Often Reversible | Usually Permanent |
|---|---|
| Obesity (weight loss) Poor sleep and untreated sleep apnea Chronic stress Heavy alcohol use Inactivity A suppressing medication (when an alternative exists) |
Testicular injury or surgical removal Genetic conditions Pituitary damage from tumors, surgery, or radiation Chemotherapy or radiation damage Significant age-related decline |
Fix a reversible cause and levels can climb back on their own. Permanent causes are still very treatable — they just usually mean testosterone replacement becomes part of ongoing health management. Our overview of treatment for testosterone deficiency walks through both paths and how doctors choose between them.
FAQs
Can stress cause low testosterone?
Absolutely. Chronic stress elevates cortisol, which suppresses testosterone. Stress management — exercise, adequate sleep, and reducing stressful situations where possible — can help restore hormonal balance, and should be part of any treatment approach if stress is a factor.
Does obesity lower testosterone?
Yes, significantly. Obesity is one of the strongest modifiable causes of low testosterone in men: excess body fat produces estrogen, which suppresses testosterone, and the accompanying insulin resistance disrupts hormonal signaling further. Weight loss can raise levels substantially — sometimes normalizing them without hormone replacement.
Can medications cause low T?
Yes. Opioids, corticosteroids, some antidepressants, and several other drug classes can suppress testosterone. If your symptoms began around the time you started a medication, mention it to your prescribing doctor and ask whether alternatives or dose adjustments exist.
Is low testosterone hereditary?
Genetics plays a role in testosterone production, but low testosterone itself isn’t strictly hereditary. If your father or male relatives had low levels, you may be predisposed — especially if you share similar health habits or body composition. Lifestyle changes often work well as prevention.
Can low testosterone be caused by diet?
Indirectly. Diets heavy in ultra-processed foods can contribute to obesity, inflammation, and hormonal dysregulation, while whole foods, adequate protein, healthy fats, and key micronutrients (zinc, vitamin D) support production. Diet alone rarely causes deficiency, but it can be part of both the problem and the solution.
Wondering whether one of these causes applies to you? The answer starts with a blood test — our testosterone testing guide explains the process. And if you want to check how deficiency might already be showing up, see our breakdown of the symptoms of low testosterone.
Your first step isn’t treatment — it’s information.
1. Get the data: a comprehensive blood panel plus a physical exam establish where you actually stand — hormones and beyond.
2. Let a doctor read the full picture: testosterone is one number among many. Your physician weighs your complete lab work, health history, and exam findings before deciding whether treatment would genuinely benefit your individual case.
References
- American Urological Association. Evaluation and Management of Testosterone Deficiency: AUA Guideline.
- Cleveland Clinic. Low Testosterone (Male Hypogonadism).
- Bhasin S, et al. Testosterone Therapy in Men with Hypogonadism: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2018.
- Urology Care Foundation. Low Testosterone.
- MedlinePlus, U.S. National Library of Medicine. Testosterone Levels Test.
Medical Disclaimer: The information on this page is for educational purposes only and is not intended as medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting, stopping, or changing any hormone therapy or medication. Individual results vary, and treatment decisions should be made between you and your doctor based on your specific medical history and needs.
National HRT Staff
Please note that the information provided in this article is for informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.