Low Testosterone and Heart Risks in Men: What the Evidence Really Shows

Low Testosterone and Heart Risks in Men

Introduction: The Real Question Behind Low Testosterone and Heart Risks in Men

The conversation around low testosterone and heart risks in men has grown louder in recent years, and much of it is confusing. Some articles suggest that falling testosterone is quietly damaging the heart. Others claim that testosterone therapy is the fix, or the danger. The truth sits in a more careful place, and it deserves a clear explanation.

Here is the honest answer up front. Low testosterone is consistently associated with a higher burden of heart disease in men, but association is not the same as cause. In many men, low testosterone appears to be a signal of underlying metabolic and vascular trouble rather than the root cause of a heart attack. That distinction matters enormously for how a man and his doctor should respond.

"Low testosterone and heart problems often show up together," says Dr. Arash Bereliani. "The mistake is assuming that one caused the other, or that raising the number will automatically protect the heart. The science simply does not support that leap."

This article walks through what testosterone does in the cardiovascular system, what low levels tend to mean, why low testosterone clusters with conditions like obesity and diabetes, and what the best available research says about whether treating it helps or harms the heart. Low testosterone, known clinically as hypogonadism, is a real medical condition with real symptoms. Understanding its relationship to heart health starts with the biology, not with a symptom checklist.

The Core Relationship: How Testosterone Affects the Heart and Blood Vessels

To understand low testosterone and heart disease, it helps to start with what testosterone does inside blood vessels and the broader metabolism. Testosterone is not only a reproductive hormone. It has measurable effects on the cardiovascular system, and those effects are one reason researchers have studied it so closely.

One of testosterone's roles involves vascular tone, the ability of blood vessels to relax and widen. Testosterone appears to support the healthy function of the endothelium, the thin inner lining of every artery. Endothelial function is a foundation of cardiovascular health. When the endothelium works well, arteries dilate properly, blood flows smoothly, and the vessel wall resists the earliest steps of plaque formation. When endothelial function declines, the stage is set for atherosclerosis, the gradual buildup of plaque that narrows and stiffens arteries.

Testosterone also interacts with metabolism in ways that touch the heart. It influences insulin sensitivity, which is the body's ability to use insulin efficiently to manage blood sugar. Lower testosterone tends to accompany reduced insulin sensitivity. It plays a part in body composition, favoring lean muscle over fat storage. It has been studied for its relationship to lipid profiles, the balance of cholesterol particles in the blood. And it appears connected to inflammatory markers, the signals of low-grade inflammation that contribute to vascular damage over time.

The vascular biology is visible in imaging research. A prospective study by Muller and colleagues found that free testosterone was inversely related to the progression of common carotid artery intima-media thickness over four years in elderly men with a mean age of 77 years. Intima-media thickness is a measurement of the innermost layers of the carotid artery wall, and it is a well-established early marker of atherosclerosis. In plain terms, the men with lower free testosterone tended to show more thickening of the artery wall over time. That is a meaningful observation about the vascular environment, even though it does not by itself prove that raising testosterone would reverse the trend.

Dr. Bereliani puts the mechanism in perspective. "Testosterone touches many of the same systems that drive heart disease," he explains. "That overlap is exactly why the hormone and the heart are so tangled together, and why we have to be careful about assigning blame."

What Low Testosterone Actually Means for a Man's Heart Risk

Epidemiological studies, the kind that track large groups of men over years, consistently link lower testosterone with more cardiovascular disease. Translating that into low testosterone cardiovascular risk for an individual man requires two things: the actual findings, and honest context about what they mean.

The imaging and mortality data are striking. In the Rotterdam study, men in the highest testosterone tertile had a 60% to 80% lower risk of severe aortic atherosclerosis after adjustment for age and cardiovascular risk factors. A prospective study by Laughlin, Barrett-Connor, and Bergstrom, which followed 794 men aged 50 to 91 for two decades, found that men with total testosterone below 241 nanograms per 100 milliliters were about 40% more likely to die than men with higher androgen levels. And Khaw and colleagues found that men in the highest testosterone quartile had a 30% lower risk of death than those in the lowest quartile.

These numbers describe a real and repeated pattern. Lower testosterone tracks with more atherosclerosis and higher mortality, including deaths related to cardiovascular disease and events such as myocardial infarction. But here is the point that most articles skip, and it is the most important one.

Association is not causation. When two things appear together, it does not prove that one produced the other. Low testosterone may be a marker of poor cardiovascular health, a warning light on the dashboard, rather than the engine problem itself. A warning light tells you to look under the hood. It does not mean unplugging the light fixes the car.

"Finding low testosterone in a man with heart disease tells us he is at higher risk," says Dr. Bereliani. "What it does not tell us is that the low testosterone caused the heart disease, or that correcting it will undo the damage. Those are separate questions, and the evidence answers them differently."

Context also matters when comparing risk factors. The established drivers of heart disease, including smoking, high blood pressure, and elevated LDL cholesterol, have decades of causal evidence behind them and clear treatment benefits. Low testosterone does not yet stand on that same footing. It belongs in the picture, but as one thread in a larger cardiometabolic story, not as a lone culprit.

Shared Risk Conditions: Obesity, Diabetes, Metabolic Syndrome, and Low Testosterone

One reason low testosterone heart disease research is so tangled is that low testosterone rarely travels alone. It tends to cluster with obesity, type 2 diabetes, and metabolic syndrome, and these conditions influence one another in a two-way loop.

Metabolic syndrome is a group of findings that occur together: excess abdominal fat, elevated blood pressure, elevated blood sugar, high triglycerides, and low HDL cholesterol. Each of these independently raises cardiovascular risk. Men with metabolic syndrome frequently have lower testosterone, and men with lower testosterone are more likely to develop metabolic syndrome. The relationship runs in both directions.

The biology helps explain the loop. Excess body fat, particularly around the abdomen, increases the conversion of testosterone into estrogen and disrupts the hormonal signals that tell the body to produce testosterone. So gaining fat can suppress testosterone. At the same time, low testosterone favors fat storage and reduced insulin sensitivity, which can worsen weight and blood sugar. Each condition nudges the other in the wrong direction.

This is central to understanding the heart connection. When a man has low testosterone alongside obesity, diabetes, or metabolic syndrome, his elevated cardiovascular risk may be driven largely by those metabolic conditions. The low testosterone may be more a reflection of that cardiometabolic disease than an independent cause of heart attacks. This is why many specialists view low testosterone in these men as a marker worth investigating rather than a target to be treated in isolation. Addressing the underlying metabolic health, through weight management, blood sugar control, and cardiovascular risk reduction, sometimes improves testosterone levels as well.

Does Treating Low Testosterone Help or Harm the Heart

The question of low testosterone treatment and heart disease is where patients most want a clear yes or no, and where honesty about uncertainty matters most. For years, the safety of testosterone replacement therapy for the heart was genuinely unclear, and concern was high enough that the Food and Drug Administration issued a warning about prescription testosterone therapy in 2014.

The most important recent evidence comes from the TRAVERSE trial. This large randomized study enrolled over 5,200 men with low testosterone and either existing or high cardiovascular risk, assigning them to testosterone replacement therapy or placebo and following them for about 33 months. It found testosterone therapy noninferior to placebo for a combined outcome of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke, with a hazard ratio of 0.96. In plain language, over roughly three years, men on testosterone did not have more major cardiac events than men on placebo.

That is reassuring, but it must be read carefully. Noninferior means not worse. It does not mean testosterone protected the heart or reduced heart attacks. And the trial did surface safety signals that deserve attention. Pulmonary embolism, a blood clot in the lungs, occurred in 0.9% of the testosterone arm versus 0.5% of the placebo arm. The trial also noted a higher rate of atrial fibrillation, an irregular heart rhythm, among men taking testosterone. These findings mean the therapy is not free of cardiovascular considerations.

Broader reviews echo this mixed picture. The Androgen Society published a position paper that reviewed 19 meta-analyses on testosterone therapy, reflecting how much analysis has gone into this question and how varied the conclusions have been. On cholesterol specifically, Mayo Clinic doctors reviewed 30 trials of testosterone replacement therapy and found no overall effect of hormone treatment on cholesterol levels, which argues against the idea that therapy meaningfully improves lipid-related heart risk.

Current clinical guidance reflects this caution. The Endocrine Society advises against initiating testosterone within 6 months of a major cardiovascular event or stroke. This deferral period is meaningful. It recognizes that the time immediately after a heart attack or stroke is a vulnerable window, and that starting a hormone with clotting and rhythm signals during that period is not advisable. The FDA, for its part, has approved testosterone only for men with documented hypogonadism from specific medical conditions, not as a general treatment for aging or heart protection.

"TRAVERSE was genuinely helpful, because it lowered the alarm about testosterone and heart attacks," says Dr. Bereliani. "But it did not give us permission to use testosterone to protect the heart, and it flagged real signals around blood clots and rhythm. We know the picture out to about three years. Beyond that, the honest answer is that we do not yet know."

Men and Heart Risk: Why the Male Pattern Matters

Men face cardiovascular risk in a particular way, and that pattern shapes how low testosterone should be interpreted. Men tend to develop heart disease earlier in life than women, and male cardiometabolic risk often builds through the same channels testosterone touches: abdominal fat, insulin resistance, blood pressure, and atherosclerosis. When low testosterone appears in this setting, it frequently reflects that broader male-pattern risk rather than acting as a standalone cause.

One symptom deserves special attention because it is so often misread: erectile dysfunction. Many men assume erectile dysfunction is simply a testosterone problem to be fixed with a hormone. The reality is more important for the heart. Erectile dysfunction can be an early warning sign of vascular disease, because the small arteries that supply the penis can show trouble before the larger coronary arteries do. In that sense, erectile dysfunction may be the first visible sign of atherosclerosis anywhere in the body.

The evidence complicates the simple testosterone story further. The Massachusetts Male Aging Study surveyed 625 randomly selected men aged 40 to 70 and found that 41% had moderate to severe erectile dysfunction, with no link found between erectile dysfunction and total testosterone, bioavailable testosterone, or sex hormone binding proteins. In other words, in that study, erectile dysfunction did not track with testosterone levels at all. This is exactly why a man with new erectile dysfunction is better served by a cardiovascular evaluation than by reaching for a testosterone product on the assumption that a low hormone is to blame.

"When a man comes in with erectile dysfunction, the smart move is to ask what the arteries are telling us," says Dr. Bereliani. "It can be the earliest whisper of heart disease, and that is a warning worth listening to."

What to Do Next: Testing, Symptoms, and Heart Risk Evaluation Together

Because low testosterone and heart risk are so intertwined, the sensible approach evaluates them together rather than in isolation. This section explains the general landscape. It is not medical advice, and specifics belong to a conversation with a personal physician.

Testosterone is not measured casually. Levels vary through the day and are highest in the morning, so a fasting early-morning blood test is the standard starting point. Because a single reading can be misleading, a true diagnosis of hypogonadism generally requires more than one low measurement, taken correctly, paired with symptoms that fit. Symptoms that may prompt an evaluation include persistent fatigue, low libido, reduced muscle mass, mood changes, and erectile difficulties, though these can have many causes unrelated to testosterone.

What makes the evaluation genuinely useful is looking at heart risk at the same time. A thorough assessment considers lipids, blood pressure, and blood glucose alongside any testosterone testing, because those factors carry far more established weight in predicting cardiovascular events. A man learning he has borderline low testosterone gains far more by also learning where his blood pressure, cholesterol, and blood sugar stand.

If a doctor and patient do decide to pursue testosterone replacement therapy, monitoring becomes part of the plan. One key measure is hematocrit, the percentage of blood volume made up of red blood cells. Testosterone can raise hematocrit, and thicker blood can increase clotting risk, so this value is typically checked over time. This is one more reason testosterone is a prescription medication that calls for oversight, not a casual supplement.

That point leads directly to over-the-counter testosterone boosters. These products are widely marketed and easy to buy, but they are not a reliable option for a man concerned about genuine hypogonadism or heart risk. They are not held to the same standards as prescription therapy, their ingredients and effects are inconsistent, and they can create a false sense of action while leaving the real cardiometabolic picture unaddressed. A man who suspects low testosterone is far better served by a proper evaluation than by a bottle from a shelf.

Frequently Asked Questions

Can low testosterone cause heart palpitations?

Low testosterone has not been clearly proven to cause heart palpitations. The research connects low testosterone to broader cardiovascular risk, but not to a direct role in causing a racing or fluttering heartbeat. Interestingly, palpitations have sometimes been reported as a possible effect after starting testosterone therapy, which is a separate matter from having low levels to begin with. Anyone experiencing palpitations should have them evaluated by a clinician, since heart rhythm deserves a proper assessment regardless of hormone levels.

Can low testosterone cause heart problems?

Low testosterone is linked to a higher burden of heart disease risk factors, but whether it directly causes heart problems remains unproven. Many studies show that men with low testosterone tend to have more cardiovascular disease, yet the data on whether low levels actually cause that disease are mixed. Low testosterone often reflects underlying conditions such as obesity or diabetes that independently harm the heart. Current guidance does not support treating low testosterone simply to prevent heart disease, and any decision should be individualized with a doctor.

Is testosterone bad for your heart?

High quality evidence does not show that testosterone therapy universally harms the heart. In men with low testosterone and elevated cardiovascular risk, a large randomized trial found testosterone therapy was not worse than placebo for major cardiac events over about three years. That said, the same body of research has flagged possible signals around blood clots and irregular heart rhythm, so testosterone is not risk-free. Whether it is safe depends on the individual, including baseline heart disease, dose, and formulation, which is why it should be discussed with a clinician.

Does low testosterone cause heart disease or is it just associated with higher risk?

Current evidence shows low testosterone is strongly associated with higher heart disease risk, but it has not been established as a direct cause. In many men, low testosterone appears to be a marker of underlying metabolic and vascular disease rather than the thing driving heart attacks. This distinction is central: finding low testosterone identifies a man at higher risk, but it does not prove the hormone caused the problem or that raising it would reverse the risk. The causal question remains genuinely unsettled.

Is testosterone therapy safe for men who have heart disease or have had a heart attack?

Testosterone therapy should not be started soon after a major cardiac event, and the Endocrine Society advises against beginning it within six months of a heart attack or stroke. The period right after such an event is a vulnerable window, and testosterone carries signals related to clotting and heart rhythm that make caution important. For men with stable heart disease, the decision is individualized and requires weighing personal risks and benefits with a cardiologist. Testosterone is not used as a treatment for heart disease itself.

What did the TRAVERSE trial show about testosterone therapy and heart safety?

The TRAVERSE trial found that testosterone therapy was not worse than placebo for major cardiac events in men with low testosterone and high cardiovascular risk over roughly three years. This was reassuring, because it eased longstanding worry that testosterone might trigger heart attacks or strokes. However, the trial did not show that testosterone protects the heart, and it did note higher rates of pulmonary embolism and atrial fibrillation in the testosterone group. Its findings apply to about three years of follow-up, so longer-term effects remain unknown.

How is low testosterone diagnosed and what counts as a true deficiency?

Low testosterone, or hypogonadism, is diagnosed through a fasting early-morning blood test, usually repeated, combined with symptoms that fit the condition. Because levels swing during the day and a single reading can mislead, doctors generally require more than one confirmed low measurement before making the diagnosis. Symptoms alone are not enough, and blood levels alone are not enough; the diagnosis rests on both together. A qualified physician interprets the results in the full context of a man's health rather than relying on one number.

The Bottom Line

The relationship between low testosterone and heart risk in men is real, but it is complex, and it is still evolving. Low testosterone consistently travels with more atherosclerosis and higher cardiovascular risk, yet much of that connection appears to reflect shared conditions like obesity, diabetes, and metabolic syndrome rather than testosterone acting as a lone cause. The best recent trial suggests therapy is not clearly harmful to the heart over about three years, while also flagging signals worth respecting, and it stops well short of showing any heart benefit.

What this means for an individual man cannot be settled by a headline or a lab value. Every man's cardiometabolic picture is different, and general information like this cannot substitute for a personal evaluation. A cardiologist or endocrinologist is the right partner for weighing testosterone testing, symptoms, and heart risk factors together, and for deciding what, if anything, to do about them. Men with questions about their own heart health and hormone levels are encouraged to discuss them with a qualified physician.

About Dr. Arash Bereliani

Dr. Arash Bereliani is a board-certified cardiologist known for a preventive, whole-person approach to heart health. His work focuses on identifying and reducing cardiovascular risk early, integrating advanced diagnostics with lifestyle, metabolic, and hormonal factors that influence the heart. He is dedicated to translating complex cardiovascular science into clear, practical guidance that patients can understand and act on with their own physicians. Through his educational writing, Dr. Bereliani aims to help men and women make informed, honest decisions about their cardiovascular health.

For more information please visit: https://www.drbereliani.com/