Testosterone is the primary male sex hormone that is important for physical and sexual development. While testosterone is essential for health, there have been some concerns that high testosterone levels could negatively impact heart health. This article will examine the evidence on the relationship between testosterone and heart health, looking at the potential risks as well as the benefits.
What is testosterone?
Testosterone is an androgen (male sex hormone) that is mainly produced by the testicles in men and the ovaries and adrenal glands in women. Although testosterone is commonly associated with males, it is an important hormone for both sexes. In men, testosterone plays a key role in the development of male reproductive tissues and promoting secondary sexual characteristics such as increased muscle mass, bone mass, and growth of body hair. It also regulates sex drive, the production of sperm, fat distribution, and red blood cell production.
In women, testosterone is produced at much lower levels but has important functions related to muscle mass and strength, bone density, libido, and metabolism. Levels of testosterone peak during adolescence and early adulthood. After age 30, testosterone levels gradually decrease in both men and women.
How does testosterone affect the heart?
Testosterone can influence heart health in several ways. Some key effects include:
- Increasing red blood cell production – Testosterone stimulates the production of red blood cells, which carry oxygen. More red blood cells can thicken the blood and increase risk of clotting.
- Affecting cholesterol levels – Testosterone tends to decrease HDL (“good”) cholesterol levels. Low HDL has been associated with increased risk of heart disease.
- Impacting heart muscle cells – Testosterone may cause increased growth of heart muscle cells and increased deposits of calcium in the coronary arteries.
- Risk of heart rhythm problems – High testosterone levels may increase risk of arrhythmias such as atrial fibrillation, possibly by altering cardiac electrical activity.
By affecting these cardiovascular functions, testosterone may negatively impact heart health, particularly at higher concentrations.
Does testosterone increase heart disease risk?
A number of studies have looked at the effects of testosterone levels on heart attack, stroke, and mortality risk. However, the findings have been mixed.
Some studies have found that higher natural testosterone concentrations are associated with increased risk of adverse cardiovascular events and death. For example, a 2010 analysis of over 11,000 men found that those with total testosterone levels in the highest quarter had a 30% greater risk of developing cardiovascular disease over a 7-year period compared to men with levels in the lowest quarter.
However, other studies have not found a clear correlation between testosterone levels within the natural range and heart disease. A 2010 review did not find a strong link between endogenous testosterone levels and death from heart disease or stroke. A 2019 study found no connection between naturally-occurring testosterone levels and plaque buildup in the arteries.
When it comes to testosterone prescribed as hormone replacement, a 2010 clinical review reported that the evidence on heart disease risk was unclear. Some studies found increased risk while others did not.
Overall, the current research suggests that there may be a connection between higher testosterone levels and increased heart disease events, but the relationship is complex. Many experts believe that only very high testosterone levels, well beyond the normal range, carry significant cardiovascular risk.
Does testosterone therapy increase risk?
Testosterone levels naturally decline in men as they age, and testosterone replacement therapy can be used to help boost levels. The effects of testosterone therapy on heart health have been studied extensively due to concerns that it may increase heart disease risk.
Some studies have found that testosterone therapy is associated with a greater incidence of cardiovascular events. For example, a study of over 55,000 men found double the rate of heart attacks among men receiving testosterone therapy compared to men not receiving it.
However, other studies have not shown elevated heart risk, or have found increased risk only among men with pre-existing heart conditions. A 2019 meta-analysis concluded that testosterone therapy does not significantly increase risk of heart attack, stroke, or mortality even among high risk men with known heart disease.
Based on the current evidence, testosterone therapy appears to have low cardiovascular risk in most men but may increase problems in those with pre-existing heart conditions. Careful screening and monitoring of heart health is important for men on testosterone therapy.
Can testosterone help the heart?
While testosterone may potentially increase heart risks at very high levels, maintaining normal testosterone levels is important for cardiovascular health in men. Some of the beneficial heart effects of testosterone include:
- Healthy cholesterol levels – Testosterone helps regulate cholesterol by reducing LDL (“bad”) cholesterol.
- Reduced plaque buildup – Testosterone may help prevent atherosclerosis by reducing inflammation.
- Better heart muscle strength – Testosterone strengthens cardiac muscle contraction.
- Decreased obesity – Testosterone plays a role in fat metabolism and reducing obesity.
- Improved oxygenation – Testosterone increases red blood cell production.
For men with abnormally low testosterone, testosterone replacement therapy may provide some benefits for heart health by restoring levels to normal.
How do anabolic steroids impact the heart?
Anabolic steroids are synthetic derivatives of testosterone that are sometimes abused, especially by athletes, to try to increase strength and muscle mass. The use of anabolic steroids can definitely harm heart health.
Some of the negative cardiovascular effects of anabolic steroid abuse include:
- Hypertension
- Increased cholesterol levels
- Blood clotting
- Enlarged heart muscle
- Heart arrhythmias
- Heart attacks
- Sudden cardiac death
These serious heart conditions are triggered by excessively high testosterone levels well above the normal range. AAS abuse can raise testosterone to 100-1000 times higher than physiological levels. At these supraphysiological dosages, testosterone can remodel heart tissue and damage blood vessels.
Even short-term use of anabolic steroids can potentially cause permanent cardiovascular damage. Long-term abuse substantially raises the risk of heart disease and stroke.
Key takeaways
- Testosterone is an important hormone but can potentially impact heart health at very high levels.
- High natural testosterone has been linked to increased heart disease in some studies but findings are mixed.
- Testosterone therapy has low cardiac risk for most men without pre-existing conditions.
- Maintaining normal testosterone is beneficial for heart health while abnormally low levels may impair heart function.
- Anabolic steroid abuse can definitely lead to heart damage due to extremely high testosterone levels.
Conclusion
Testosterone is an essential hormone, but optimal levels are vital for cardiovascular health. Normal physiological levels play an important role in regulating cholesterol, blood oxygenation, and other factors that influence heart function. However, research indicates that very high concentrations of testosterone can potentially have adverse effects by increasing clotting risk, impairing cholesterol, and promoting heart muscle growth.
Findings on the impact of testosterone on heart disease have been mixed, with some studies implicating high testosterone levels as a risk factor. However, the relationship is complex. Many experts believe that only extremely high concentrations well outside the normal range carry serious heart risks.
Testosterone therapy appears to have low risk for most men, but potential heart complications are higher in those with pre-existing conditions. Anabolic steroid abuse can significantly harm the heart due to the extremely elevated testosterone levels.
Overall, maintaining testosterone within a normal physiological range is important for optimal heart health in men. Very high levels from performance enhancing drugs or even naturally may pose cardiovascular risks. However, low testosterone can also impair heart function. Talk to your doctor about managing testosterone levels, especially if you have heart disease risk factors or use testosterone therapy.