Guys, here’s how testosterone can affect your overall health

Testosterone, a key male hormone, does a lot for the body and has a huge impact on overall health. Beyond shaping body composition, this potent androgen supports mental health, intimate function, and metabolic health. It fuels reproductive processes like drive, sperm production, and intimate function while also influencing cardiovascular health by helping to regulate fat distribution, blood sugar, and cholesterol. When kept within a healthy range, testosterone can even lower the risk of chronic conditions like type 2 diabetes.

Since testosterone has so many big jobs, it’s no wonder that when its levels dip too low — as is true in men with hypogonadism — your whole system can feel off. Ahead, we’ll explore the surprising effects of testosterone on health, the telltale signs your levels may be off, and what you can do to restore hormonal balance.

Testosterone is the primary male hormone, or androgen. The privates (and, in smaller amounts, the adrenal glands) are the primary producers of the hormone. Testosterone is essential for the development of reproductive organs like the privates’ parts, and the androgen also drives secondary characteristics such as muscle mass, body hair growth, and genital development. In women, the ovaries produce small amounts of testosterone.

The body regulates testosterone through the hypothalamic-pituitary-gonadal (HPG) axis. Here’s how:

• The hypothalamus in the brain releases gonadotropin-releasing hormone (GnRH).

• GnRH prompts the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

• LH signals the Leydig cells in the testes to produce testosterone, while FSH works on the Sertoli cells to produce sperm.

• A negative feedback loop regulates most hormones, including testosterone. When testosterone levels rise too high, the brain receives signals to lower production. When levels drop, the brain triggers an increase in testosterone production.

For men, testosterone production starts in the womb, surges during puberty, peaks in early adulthood, and then gradually declines with age.

The Role of Testosterone for Each Gender

Women produce testosterone, but men make a lot more of it. Circulating concentrations are about 20 to 25 times higher in adult men compared to women.

Though estrogen is considered the primary female hormone, research shows that women actually produce three times as much testosterone before menopause. Similar to men, in women, testosterone can be crucial for bone density, muscle mass, mood, cognitive function, intimate health, and energy.

While testosterone is often recognized for its role in regulating drive and fertility, its benefits extend beyond what happens in the bedroom.

“Testosterone is integral to systemic health,” says Mike Bohl, MD, a general practitioner and Senior Director of Medical Content & Authority at Hims & Hers. “It drives red blood cell production, preserves bone density, and modulates muscle and fat distribution—functions that extend well beyond reproduction.”

Testosterone levels can impact how your body expends energy, how sharp your mind feels when you’re powering through your workday, and more. Healthy levels can mean more vigorous workouts, bigger muscle gains, and an active intimate life, in addition to better long-term protection against issues like osteoporosis and metabolic disease.

On the other hand, lower testosterone levels can mean more body fat, brain fog, ED, and an increased risk of cardiovascular disease.

Here are some of the surprising ways testosterone can impact men’s health.

Testosterone impacts various aspects of your physical health, including:

• Muscle mass and strength

• Bone density and structure

• Fat distribution and metabolism

• Cardiovascular health

1. Muscle Mass

As an anabolic hormone, testosterone helps preserve muscle in men by activating muscle repair cells, boosting protein synthesis, and encouraging stem cells to develop into muscle instead of fat. Lower testosterone levels are associated with less lean muscle mass, which can make it harder to maintain strength and physical performance over time.

2. Bone Density

Testosterone helps bones achieve their peak mass and is essential for maintaining bone density throughout adulthood. Research has shown that testosterone replacement therapy (TRT) is a valid treatment option to improve symptoms of low testosterone and bone mineral density, especially in men with hypogonadism who have osteopenia and osteoporosis.

3. Fat Distribution and Metabolism

Testosterone plays a crucial role in carbohydrate, fat, and protein metabolism, and, by proxy, influences body fat composition in men. Research shows that testosterone deficiency is associated with increased fat mass, impaired glucose tolerance, reduced insulin sensitivity, and elevated cholesterol, all of which are linked to metabolic syndrome, type 2 diabetes, and increased cardiovascular risk. Testosterone therapy may also improve insulin resistance while reducing body fat and cholesterol.

4. Cardiovascular Health

Research shows that testosterone therapy may lead to improved exercise capacity in men with heart failure, reduced body fat, and better insulin sensitivity, all of which contribute to elevated cardiovascular health.

5. Red Blood Cell Production

Testosterone supports healthy oxygen delivery by stimulating erythropoiesis, the process of red blood cell production in the bone marrow. Compared to men with normal testosterone levels, men with low testosterone are 5 to 13 times more likely to develop anemia, a condition of low red blood cells leading to poor oxygenation.

TRT has also been shown to boost the body’s percentage of red blood cells (hematocrit) and the oxygen-carrying capacity of those cells (hemoglobin) in men with low T.

But it’s not all about your muscles, bones, and heart health. Testosterone is also vital to mental and cognitive health, contributing to:

• Mood regulation

• Energy levels

1. Mood Regulation

Testosterone supports mood regulation by reducing anxiety, promoting confidence and assertiveness, and helping to maintain overall psychological well-being. Research links low levels with symptoms of depression and poorer quality of life. In older men with hypogonadism, symptoms may include mild fatigue, depression, hopelessness, life ending ideation, and more.

2. Energy Levels

It’s hard to feel good or think straight when you have low energy. Along with impaired function, low testosterone also has associations with fatigue. However, studies show that long-term testosterone therapy may help restore energy and reduce tiredness in men with hypogonadism.

It’s no secret that testosterone is central to intimate function. You’ve seen its effects firsthand during puberty, between changes in your body and shifts in your drive. In terms of intimate health, testosterone helps to regulate:

• Libido and desire

• Intimate function

• Sperm production and fertility

1. Libido and  Desire

Libido, or desire, refers to your interest in engaging in intimate activities. Research shows that testosterone is a driver of this natural inclination in both men and women, affecting various brain regions involved in desire, including the hypothalamus.

Low libido is one of the most commonly reported symptoms of low testosterone. Research shows that testosterone supplementation in men with hypogonadism can significantly improve intimate function, leading to a higher frequency of intimacy, more nighttime arousal, and enhanced desire.

2. Arousal Function

Beyond boosting libido, research suggests that testosterone also supports arousal by acting as a vasodilator, increasing blood flow to the privates. In men with low testosterone, restoring levels can improve intimate function. Studies show that combining testosterone therapy with ED medication (like sildenafil) can be especially effective for men who have ED and other health conditions and who don’t respond well to either treatment on its own.

3. Sperm Production and Fertility

Testosterone is also a key player in sperm production and male fertility. Studies show that producing mature sperm relies heavily on androgen action within the testes. The absence of testosterone can result in male infertility.

Unfortunately, TRT won’t help with fertility concerns. In fact, one of the major risks of TRT is infertility, and some researchers have even deemed the hormone therapy to be a contraceptive.

Fortunately, fertility-safe testosterone treatments exist, such as enclomiphene, which blocks estrogen to trick the body into producing more testosterone. This process transpires without compromising fertility.

Normal testosterone levels in men range from 300 to 1,000 nanograms per deciliter (ng/dL) of blood. The American Urological Association defines low testosterone, or testosterone deficiency, as less than 300 ng/dL.

However, some researchers advocate for raising the 300 ng/dL cutoff for younger men. This methodology argues that diagnosing low testosterone shouldn’t use a one-size-fits-all approach to testosterone deficiency.

If you sense something may be off with your testosterone levels, make an appointment with your healthcare provider to discuss your symptoms and chart out the best next steps, like taking a hormone test.

While taking a testosterone blood test is an essential first step in determining whether your testosterone levels are low, you likely won’t receive a diagnosis unless you’re also facing symptoms.

Some of the most common symptoms of low testosterone include:

• Low drive

• ED

• Decreased muscle mass

• Increased body fat

• Less body hair

• Brain fog

• Mood changes

• Low energy levels

• Male breast growth (gynecomastia)

• Hot flashes

Your low testosterone may be the result of age-related changes, congenital conditions, lifestyle habits, and more.

Understanding what’s contributing to your low levels also depends on your type of low testosterone. Primary hypogonadism indicates a problem with your privates’ ability to produce testosterone, and secondary hypogonadism suggests faulty signaling between the brain and the testes.

Causes of primary hypogonadism include:

• Congenital conditions like Klinefelter syndrome

• Privates injuries

• Undescended privates.

• Cancer treatments, like chemotherapy or radiation for prostate cancer

• Infections like mumps orchitis

Causes of secondary hypogonadism include:

• Genetic conditions like Kallmann syndrome

• Pituitary tumors or disorders

• Metabolic disorders like hemochromatosis (iron buildup)

• Being overweight or obese

• Obstructive sleep apnea

• HIV/AIDS

• Alcohol abuse

• Anabolic steroid use

Lifestyle Factors

There’s also evidence that lifestyle habits can contribute to low testosterone.

For instance, a sedentary lifestyle has associations with lower testosterone levels (and low sperm count).

Western diets high in processed foods and low in vegetables are also linked to low testosterone due to their impact on body composition.

TRT may be the household name for low-testosterone treatments, and for many men, it’s a good one. But additional options also exist.

Such options include:

• Testosterone replacement therapy. TRT comes in the form of injections, gels, pellets, pills, and patches. While versatile and highly effective, the treatment may not be appropriate for all men. In addition to increasing the risk of infertility, TRT may also cause skin reactions, high red blood cell count (which can lead to blood clots in some men), benign prostatic hyperplasia (enlarged prostate), and allergic reactions.

• Selective estrogen receptor modulators (SERMs). SERMs like enclomiphene and clomiphene disrupt the hypothalamic-pituitary-gonadal axis negative feedback loop by blocking estrogen and increasing the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). This prompts the body to make more testosterone and sperm.

• Human chorionic gonadotropin (hCG). This medication functions like LH by signaling the Leydig cells in the testes to produce more testosterone. Like enclomiphene, hCG is also a fertility-safe treatment for low testosterone.

• Healthy lifestyle changes. While lifestyle changes aren’t a direct treatment for low testosterone, they can help support healthy testosterone production. Following a nutritious diet, exercising regularly, getting enough sleep, and managing your stress levels may sound like basic habits, but they’re the building blocks to hormonal balance.

Testosterone is a powerful hormone that affects nearly every system in your body. From mood and metabolism to heart health and fertility, testosterone plays a central role in keeping your body and mind functioning well. When levels drop too low, effects can be wide-ranging, from fatigue and brain fog to increased risk of chronic disease and more.

Getting regular checkups, noticing symptoms, and having conversations with your healthcare provider can help you catch imbalances early and explore safe and effective treatments that support your long-term health.

What are normal testosterone levels for men?

Normal levels typically range from 300 to 1,000 ng/dL, though age, health, and lab methods can affect the reference range. Some experts argue that reference levels should be tailored to age groups.

Can low testosterone cause symptoms even if my levels are “normal”?

Yes. Testosterone testing is important, but doctors also consider your symptoms — like fatigue, low libido, or muscle loss — when evaluating hormone health before making a diagnosis.

Will testosterone therapy improve fertility?

It’s highly unlikely. Traditional TRT can actually reduce sperm production. Fertility-safe options, like enclomiphene or hCG, may be better choices if you’re trying to maintain fertility. You can discuss the best options for you with your doctor.

Can lifestyle changes really make a difference in testosterone levels?

Absolutely. Regular exercise, a balanced diet, adequate sleep, and stress management all help support healthy testosterone production and overall hormone balance.

Do women need testosterone, too?

Yes. Women produce much lower levels than men, but testosterone is still important for their bone strength, energy, mood, and intimate health.