Testosterone Therapy & Heart Health: New Safety Data

For years, testosterone replacement therapy, also called TRT, has been caught in the middle of a loud debate.

One side says testosterone therapy is dangerous for the heart. The other side treats it like a magic fix for every man who feels tired, foggy, or less driven than he used to.

Both extremes miss the point.

A 2024 meta-analysis published in Endocrine Practice reviewed 26 randomized controlled trials involving 10,941 men with hypogonadism. The researchers looked at major cardiovascular outcomes, including all-cause mortality, cardiovascular-related death, heart attack, stroke, congestive heart failure, atrial fibrillation, pulmonary embolism, and venous thrombosis.

Their conclusion was reassuring: testosterone replacement therapy did not significantly increase mortality or worsen cardiovascular outcomes in hypogonadal men.

That does not mean TRT is risk-free. It means the conversation needs to move from fear-based headlines to better screening, better labs, better dosing, and better follow-up.

Because testosterone therapy is not the problem when used correctly.

Bad medicine is the problem.

Table of Contents

Why Testosterone and Heart Health Became So Controversial

Testosterone affects far more than libido.

It plays a role in muscle mass, red blood cell production, mood, motivation, bone density, metabolic health, insulin sensitivity, and sexual function. When testosterone is genuinely low, men may experience symptoms like:

Low energy
Reduced libido
Erectile changes
Loss of muscle
More belly fat
Poor recovery
Brain fog
Low motivation
Depressed mood
Sleep issues

But here is where things got messy.

As “low T” marketing exploded, testosterone therapy was sometimes prescribed without enough testing, without clear symptoms, or without proper monitoring. That created understandable concern.

Some earlier observational studies suggested possible cardiovascular risk. Others showed no increased risk or even potential benefit in properly selected men. The result was confusion for patients and hesitation from providers.

And when medicine gets confusing, the internet usually makes it worse. Naturally.

That is why randomized controlled trial data matters. It helps separate signal from noise.

What the 2024 Meta-Analysis Studied

The 2024 meta-analysis by Sood and colleagues focused specifically on hypogonadal men receiving testosterone replacement therapy.

That detail matters.

This was not a study of bodybuilders abusing anabolic steroids. It was not a review of men taking random “testosterone boosters” from a gas station supplement shelf, which is apparently still something civilization allows.

The study reviewed 26 randomized controlled trials with a total of 10,941 participants. The researchers compared men receiving TRT with control groups and assessed several cardiovascular outcomes.

The outcomes included:

All-cause mortality
Cardiovascular-related mortality
Myocardial infarction, also called heart attack
Stroke
Congestive heart failure
Atrial fibrillation
Pulmonary embolism
Venous thrombosis

The researchers found no statistically significant differences between the TRT group and the control group for these major clinical outcomes.

They also performed sensitivity analyses and publication bias assessments, which supported the strength of the findings. A meta-regression analysis found no significant association between the outcomes and covariates such as age, diabetes, hypertension, dyslipidemia, and smoking.

When TRT was studied in hypogonadal men under controlled conditions, it did not appear to increase major cardiovascular events compared with control groups.

What This Means for Men Considering TRT

This study gives men and clinicians more confidence that testosterone therapy, when prescribed appropriately, does not automatically increase the risk of heart attack, stroke, or cardiovascular death.

But the key phrase is “when prescribed appropriately.”

TRT should not be used because a man wants a shortcut.

It should be considered when there are both:

Symptoms consistent with testosterone deficiency
Repeated lab testing showing low testosterone

That distinction is important.

A man can feel tired for a dozen reasons that have nothing to do with testosterone. Poor sleep, insulin resistance, thyroid issues, chronic stress, nutrient deficiencies, under-eating protein, too much alcohol, sleep apnea, depression, and overtraining can all create symptoms that look like low testosterone.

Treating the wrong problem with testosterone is not optimization. It is guessing with a prescription pad.

At 1st Optimal, we look at testosterone in context. That means reviewing symptoms, medical history, medications, lifestyle, body composition, cardiometabolic risk, and lab markers before building a plan.

The goal is not to chase a number.

The goal is to help the body perform better safely.

Low Testosterone and Cardiometabolic Risk

One reason this topic matters so much is that low testosterone often travels with other metabolic problems.

Men with low testosterone may also have:

Increased visceral fat
Insulin resistance
Higher triglycerides
Lower muscle mass
Poor sleep
Higher inflammation
Reduced exercise capacity
Higher cardiovascular risk factors

This does not mean low testosterone always causes those issues directly. Biology is not that tidy, despite everyone wanting one villain.

But low testosterone can be part of a bigger pattern.

For example, a man with belly fat, poor sleep, high fasting insulin, low free testosterone, high blood pressure, and low muscle mass does not need a one-marker solution. He needs a full cardiometabolic strategy.

That may include testosterone therapy if he qualifies, but it should also include strength training, nutrition, sleep support, blood pressure management, lipid testing, glucose control, and inflammation reduction.

TRT can be one tool.

It should not be the whole toolbox.

What TRT Can Improve When a Man Is Truly Deficient

For men with confirmed hypogonadism, testosterone therapy may help improve several quality-of-life and performance-related symptoms.

Potential benefits may include:

Better libido
Improved erectile function in some men
More stable energy
Improved mood and motivation
Increased lean mass
Improved strength response to training
Better bone density
Improved anemia in some men
Better recovery

The keyword is “may.”

Not every man responds the same way. Dose, delivery method, baseline health, sleep, body fat, estrogen balance, thyroid function, nutrition, and training all influence the outcome.

A man who starts TRT but keeps sleeping 5 hours, drinking nightly, skipping protein, avoiding resistance training, and living on stress hormones should not be shocked when the results are underwhelming.

Hormones amplify the environment you put them in.

If the foundation is bad, TRT does not magically fix the house.

Why Monitoring Still Matters

The 2024 meta-analysis is reassuring, but it does not remove the need for medical monitoring.

Testosterone therapy can affect several markers that need to be watched, including:

Hematocrit
Hemoglobin
Blood pressure
Estradiol
Prostate-specific antigen, also called PSA
Lipids
Liver enzymes
Sleep apnea symptoms
Fertility status
Mood or irritability
Acne or oily skin
Fluid retention

One of the most important markers is hematocrit, which reflects the percentage of red blood cells in the blood. Testosterone can increase red blood cell production. That may help some men with anemia, but if hematocrit climbs too high, blood viscosity can become a concern.

Blood pressure also matters. The U.S. Food and Drug Administration updated testosterone labeling in 2025 after post-market ambulatory blood pressure monitoring studies confirmed that testosterone products can increase blood pressure. That does not mean every man will have a major issue, but it does mean blood pressure should be checked regularly.

This is why “set it and forget it” TRT is poor care.

A good TRT plan includes follow-up labs, symptom review, dose adjustments, and ongoing cardiovascular risk management.

Who Should Be More Careful With Testosterone Therapy?

Some men need more caution before starting TRT.

This includes men with:

Recent heart attack or stroke
Uncontrolled high blood pressure
Elevated hematocrit
Untreated severe sleep apnea
Active or metastatic prostate cancer
Severe lower urinary tract symptoms
History of blood clots
Significant heart failure
Desire for fertility in the near future

Fertility deserves special attention.

Testosterone therapy can reduce luteinizing hormone and follicle-stimulating hormone, which can lower sperm production. Men who want children soon should discuss alternatives such as enclomiphene or human chorionic gonadotropin, depending on their clinical situation.

This is another reason proper evaluation matters. A man should not find out six months into therapy that his “optimization plan” worked against his family plan.

That is not optimization. That is sloppy.

What About the TRAVERSE Trial?

The 2024 meta-analysis fits with another major study: the TRAVERSE trial, published in The New England Journal of Medicine in 2023.

TRAVERSE studied middle-aged and older men with hypogonadism who either had existing cardiovascular disease or were at high cardiovascular risk. The trial found that testosterone therapy was noninferior to placebo for major adverse cardiovascular events.

In practical terms, the trial did not show an increased risk of major heart events like heart attack, stroke, or cardiovascular death in appropriately selected and monitored men.

However, some adverse events, including atrial fibrillation and pulmonary embolism, were observed more often in the testosterone group in TRAVERSE. That does not erase the reassuring cardiovascular outcome data, but it does remind us that patient selection and monitoring are not optional.

The best interpretation is not “TRT is dangerous.”

It is also not “TRT is risk-free.”

The better interpretation is: TRT appears cardiovascularly safe for many properly diagnosed men when prescribed and monitored carefully, but it still requires individualized medical oversight.

Boring? Maybe.

Accurate? Yes.

What Most Men Get Wrong About Testosterone

Most men do not need more hype.

They need better data.

Here are the common mistakes we see:

Mistake 1: Testing testosterone once

Testosterone fluctuates. Sleep, stress, calorie intake, alcohol, illness, medications, and timing of the blood draw can affect results.

A proper evaluation usually includes morning testing and confirmation when levels are low.

Mistake 2: Only checking total testosterone

Total testosterone is useful, but it is not the whole picture.

A better panel often includes:

Total testosterone
Free testosterone
Sex hormone-binding globulin, also called SHBG
Estradiol sensitive assay
Luteinizing hormone
Follicle-stimulating hormone
Prolactin
PSA
Complete blood count
Comprehensive metabolic panel
Lipid panel
Hemoglobin A1c
Fasting insulin
Thyroid markers when clinically appropriate

Symptoms plus the right labs give a much clearer picture.

Mistake 3: Ignoring sleep apnea

Untreated sleep apnea can crush testosterone, increase blood pressure, worsen insulin resistance, and raise cardiovascular risk.

Starting TRT while ignoring sleep apnea is like putting premium fuel in a car with the parking brake on.

Mistake 4: Chasing high numbers

More testosterone is not always better.

The goal is not to create supraphysiologic levels. The goal is to restore healthy function while minimizing side effects.

Mistake 5: Forgetting lifestyle

TRT works best when paired with the habits that support hormone signaling:

Strength training 3–4 days per week
Daily walking
Protein-forward meals
Better sleep timing
Alcohol reduction
Blood sugar control
Stress management
Enough calories and micronutrients
Cardiovascular conditioning

Hormone therapy should build on the basics, not replace them.

A Smarter Way to Evaluate Low Testosterone

A high-quality testosterone evaluation should answer several questions:

Are symptoms consistent with testosterone deficiency?
Are testosterone levels repeatedly low?
Is the issue primary or secondary hypogonadism?
Are there reversible drivers such as obesity, sleep apnea, medications, under-eating, overtraining, or thyroid dysfunction?
Is fertility a priority?
Are cardiovascular risk factors controlled?
Is prostate screening appropriate?
What delivery method fits the patient best?
What follow-up schedule is needed?
What markers define success beyond testosterone numbers?

That last question matters.

Success should not be judged only by a lab value.

It should include how the man feels, performs, sleeps, trains, recovers, and functions sexually. It should also include whether blood pressure, hematocrit, lipids, glucose, and inflammatory risk are moving in the right direction.

What This Study Means for High-Performing Men

Many high-achieving men wait too long to address symptoms.

They push through fatigue. They blame aging. They drink more coffee. They train harder. They work longer. They tell themselves they are fine while their body quietly sends invoices.

Low testosterone can show up gradually.

You may notice:

Less drive
Less morning energy
More belly fat
Fewer morning erections
Lower libido
Worse recovery
More irritability
Poor sleep
Less strength in the gym
Brain fog that makes work harder

These symptoms are common, but they are not something to ignore.

The answer is not automatically TRT.

The answer is better testing.

Once you know what is happening with testosterone, thyroid, insulin, inflammation, lipids, blood count, nutrient status, and recovery markers, you can make a smarter plan.

That plan may include testosterone therapy.

It may include lifestyle changes first.

It may include sleep apnea screening, thyroid support, weight loss therapy, nutrition changes, or cardiometabolic risk management.

The right plan depends on the data.

Bottom Line: TRT Looks Safer Than the Headlines Suggest

The 2024 meta-analysis adds to a growing body of evidence showing that testosterone replacement therapy does not appear to increase major cardiovascular events in appropriately diagnosed hypogonadal men.

That is good news.

But it does not mean men should get casual with hormones.

TRT should be treated like a medical therapy, not a wellness trend. The safest results come from proper diagnosis, individualized dosing, routine monitoring, and a full-body strategy that includes sleep, nutrition, training, metabolic health, and cardiovascular risk management.

At 1st Optimal, we do not guess with hormones.

We test, interpret, personalize, and monitor.

If you are dealing with low energy, low libido, stubborn belly fat, poor recovery, brain fog, or symptoms of low testosterone, the next step is not to panic or self-prescribe.

The next step is better data.

Ready to take the next step?

Ready to find out what your hormones, metabolism, and cardiovascular markers are actually doing?

Book a free consult with 1st Optimal and get a personalized plan built around your labs, symptoms, goals, and long-term health.

FAQ:

Does testosterone therapy increase heart attack risk?

Current evidence from randomized controlled trials does not show a significant increase in heart attack risk when TRT is used in properly diagnosed hypogonadal men and monitored appropriately. Men with recent cardiovascular events or uncontrolled risk factors still need individualized medical review.

Is TRT safe for men with heart disease?

TRT may be appropriate for some men with cardiovascular risk, but it depends on the full clinical picture. Men with known heart disease should be evaluated carefully, including blood pressure, hematocrit, lipids, glucose, symptoms, medications, and recent cardiac history.

What labs should be checked before TRT?

A strong baseline panel often includes total testosterone, free testosterone, SHBG, estradiol sensitive assay, LH, FSH, prolactin, PSA, CBC, CMP, lipid panel, hemoglobin A1c, fasting insulin, and thyroid markers when appropriate.

Can TRT raise blood pressure?

Yes, testosterone products can increase blood pressure in some men. Blood pressure should be checked before treatment and monitored during therapy.

Does TRT affect fertility?

Yes. Testosterone therapy can suppress sperm production. Men who want children in the near future should discuss fertility-preserving options before starting treatment.

Is low testosterone just part of aging?

Testosterone can decline with age, but symptoms should not be dismissed as “just aging.” Low testosterone may also be linked to sleep apnea, insulin resistance, obesity, medications, stress, thyroid issues, or other medical factors.

What is the safest way to start TRT?

The safest approach includes confirming symptoms, repeating morning testosterone testing, reviewing cardiovascular and prostate risk, checking baseline labs, choosing the right treatment option, and monitoring follow-up labs regularly.

References

Educational only, not medical advice. Always work with a qualified medical provider before starting, stopping, or changing hormone therapy.

Testosterone Therapy and Heart Health: What Men Need to Know