Testosterone: What It Is and How It Affects Your Health

Testosterone is a hormone produced in both men and women. It plays an important role in muscle growth, bone strength, sexual health, mood, and energy levels. Both low and high testosterone levels can affect your physical and reproductive health, making hormonal balance essential for overall well-being. 

So, what is testosterone?  It's a common misconception that testosterone is "the male hormone," but this vital chemical messenger plays essential roles in both men and women. From supporting muscle mass and bone strength to influencing mood, sexual function, and cognitive health. 

Testosterone and its synthetic analogs have drawn attention through sports doping controversies, where their misuse to enhance strength and recovery has raised concerns about unfair competition. These controversies have brought attention to hormone misuse—a concern that extends beyond sports. 

Aggressive marketing of testosterone replacement therapy (TRT) has raised concerns about its use without a confirmed medical need. While TRT has a role in treating testosterone deficiency, unnecessary use comes with its own set of risks. 

Together, these concerns have encouraged interest in non-hormonal approaches to supporting healthy testosterone levels, including emerging research on geranylgeraniol (GG). 

However, being a supplement does not make GG a proven substitute for TRT; its potential benefits and safety need to be evaluated on their own evidence. 

In this blog, we'll explore what testosterone is, its impact on overall health, and evidence-based strategies for maintaining optimal levels.   

What Is Testosterone? The Science Behind the Hormone  

Testosterone is a sex hormone that belongs to the androgen category and is responsible for the development and maintenance of male characteristics in the body. It is a steroid chemically made from cholesterol.   

What Produces Testosterone in Males and Females? 

It is naturally produced in the sex organs, the gonads (testes in men and ovaries in women), and in small amounts by the adrenal glands. While women make it in significantly lesser amounts, both men and women require it for healthy physiological functioning.  

How does Your Body Controls Testosterone Production 

Testosterone is synthesized from cholesterol via a series of enzyme reactions. Its production is controlled by a complex feedback system known as the hypothalamic-pituitary-gonadal (HPG) axis involving your hypothalamus, pituitary glands (in the brain), and the gonads. Your adrenal glands are influenced by the hypothalamic-pituitary-adrenal (HPA) axis.   

Normal Testosterone Levels in Healthy Adults   

It is responsible for carrying out important functions, such as muscle maintenance, bone strength, and libido, despite lower levels in women.

Note: n the US, labs usually report testosterone in nanograms per deciliter (ng/dL). To convert nmol/L to ng/dL, multiply by 28.84. 

Normal Testosterone for Men by Age 

When considering the normal testosterone level in men by age, remember that levels generally decline as men get older, and reference ranges vary between laboratories. 

There is no single chart that fits every man, testosterone rises during puberty, peaks in early adulthood, then gradually declines, so your result should be interpreted using your lab's range together with your symptoms and overall health 

Testosterone Levels in Women 

Women's testosterone peaks in early adulthood and declines gradually with age, by around 40, average levels are roughly half those of the early 20s. Unlike estrogen, testosterone doesn't fall abruptly at natural menopause, as ovaries keep producing some androgens with time. 

When testosterone travels through your bloodstream, it doesn't exist in just one form. Understanding this distinction is crucial for anyone looking to optimize their hormonal health.  

Free Testosterone vs. Bound Testosterone: What's the Difference?  

Most of your testosterone, about 95 to 98 percent, is actually bound to proteins, particularly sex hormone-binding globulin (SHBG) and albumin. These proteins act as carriers that transport testosterone through your blood, but it's bound, so it remains inactive and can't do its job.  

Only the remaining 2 -5 %that exists unbound or free, is actually actively working for you. Free testosterone can easily enter your cells, directly influencing several vital functions in the body. This is the form that makes you feel the effects of healthy testosterone levels.  

Why this matters for your health  

You might have normal total testosterone (free + bound) levels on a blood test, yet still experience symptoms like low energy, reduced muscle mass, or decreased libido. Why? That's because your free testosterone is low!   

Studies consistently show that free testosterone levels correlate much better with real-world outcomes—like how strong you feel, your bone density, and your sexual function—than total testosterone numbers alone. (scientists call it “free hormone hypothesis”)  

This is particularly important for men experiencing borderline symptoms or those whose total testosterone appears normal but who still feel "off." Measuring free testosterone can reveal the true picture of your hormonal health.  

Now that we understand what testosterone is, what normal levels look like, and that only the free form of testosterone is actually at work, you might be wondering, what exactly does this hormone do in your body? Let's find that out.   

How does testosterone affect the body?  

You might be surprised to learn just how much testosterone affects your body. Let's learn more about its various impacts and functions in the body:  

Role of the testosterone hormone   

Here are the key testosterone benefits for males and females: 

1] Sexual Function and Reproductive Health   

Testosterone plays a crucial role in sexual health for both men and women, affecting  

A drop in its levels is closely linked to a drop in sexual desire (libido) and satisfaction, along with challenges in sexual performance for men.  

Let's explore how this hormone shapes masculine characteristics from before birth through adulthood.   

2] Development of Male Characteristics  

Testosterone directs the development of male characteristics, including:  

For adult females, it ramps up libido. Most of the testosterone produced in the ovaries is converted to estradiol, the primary female sex hormone, and is not involved in the development of female characteristics.   

Also Read: How Estrogen Affects the Female Body: Changes Over Time  

While testosterone's role in sexual development is well-known, people are most interested in its effects on physical strength and appearance, at least most of the time.  

3] Muscle Development and Maintenance   

Want those biceps to pop? One of the most recognized roles of testosterone is in muscle development (anabolic effect), as it is involved in muscle protein synthesis in both normal and elderly males, which is required for:  

Research shows that men with low testosterone levels can see a significant increase in muscle mass and a decrease in fat mass, especially when they pair supplementation with resistance training.    

Just as testosterone helps build strong muscles, it also plays a crucial role in maintaining the framework that supports those muscles—your bones.   

4] Bone Health and Density    

Testosterone plays a crucial role in maintaining bone health throughout our lives. It promotes bone formation, decreases bone breakdown, and regulates growth factors, which help maintain our bone mineral density. This is particularly required as we get older; lower hormone levels can lead to:  

Studies indicate that men with low testosterone levels face a much greater risk of osteoporosis and fractures.    

Also Read: The Science Behind Geranylgeraniol: Muscle and Bone Health Explained   

Your brain, it turns out, is just as responsive to this hormone as your muscles and bones.   

5] Cognitive Function and Mood  

Did you know that testosterone affects your mood and cognitive function? Let's find out how.   

Well, your brain is packed with testosterone receptors, especially in areas linked to thinking and emotions. This explains how it affects your  

Research suggests that lower testosterone levels can lead to poorer cognitive performance in older men.    

Also Read: Exploring Astaxanthin & Tocotrienols for Brain Health Support: Research Insights  

 Your heart health is also closely tied to your hormone levels, though this relationship is more complex than you might expect.   

6] Heart Health   

The testosterone and heart health connection is quite complex and still under investigation. However, studies suggest that maintaining healthy levels proves beneficial for blood vessel function, improving blood flow, supporting ideal lipid profiles, reducing inflammation, and enhancing heart function.   

Research indicates that low testosterone levels have been associated with worsening symptoms of heart failure, although the precise cause-and-effect relationship is still being investigated.    

Also Read: Astaxanthin and Heart Health: A Natural Ally in Cardiovascular Wellness   

Testosterone's cardiovascular benefits extend beyond just heart function. This hormone also plays a role in your blood itself.   

6] Role in Red Blood Cell Production  

Testosterone increases the production of red blood cells (the process is called erythropoiesis). This happens through different processes, like  

This explains why males typically have higher hematocrit levels than females. Testosterone deficiency results in a 10% to 20% decrease in the blood hemoglobin concentration, which can result in anemia.   

With all these essential functions, you might think that more testosterone is always better. However, like most things in biology, balance is key.  

7) Testosterone Role in Women 

Although produces in small amount, testosterone role is linked to bone strength, muscle mass, and healthy ovarian function in women. 

High Testosterone  

What Causes High Testosterone? 

High testosterone can be caused by certain medical conditions like polycystic ovarian syndrome (PCOS), ovarian, testicular, or adrenal tumors, and Cushing syndrome.  

Effects of High Testosterone 

Though the condition is less common, its excessively high levels can have the following untoward effects:   

The effects of insufficient testosterone can be just as concerning, if not more so. Let's explore.  

Signs of High Testosterone in Men 

Possible signs of high testosterone in a man include: 

Signs of High Testosterone in Women 

Signs of high testosterone in a woman can include: 

Low Testosterone (Male hypogonadism)  

Causes and Symptoms of Low Testosterone in men 

Low testosterone levels can be caused by aging, an unhealthy, stressful lifestyle, some genetic or medical conditions (obesity, type 2 diabetes, Klinefelter syndrome), and medications. It usually produces symptoms only in males, leading to significant health issues:  

Does Testosterone Decline with Age? 

Male testosterone levels usually drop by 1% to 2% per year beyond the age of 30, a phenomenon known as "andropause." This happens due to changes in the hypothalamic-pituitary-gonadal axis and Leydig cell function. Additionally, if your body mass index (BMI) is high, there is a strong chance that you might have low testosterone levels.   

Given the significant impact of low testosterone on health and quality of life, you're probably wondering what you can do about it.  

Supporting Healthy Testosterone Levels   

For those aiming to keep their testosterone levels in check without turning to medicines, making some lifestyle changes can be really beneficial:  

Natural Methods:  

While lifestyle changes form the foundation of healthy testosterone levels, recent research has identified some promising natural compounds that might offer additional support. One particularly interesting discovery is geranylgeraniol. 

Geranylgeraniol's Potential in Boosting Testosterone  

Geranylgeraniol (GG), a natural compound found in annatto plant seeds, is gaining attention for its potential to support testosterone levels. Research indicates that GG might help those with low testosterone production (below24nmol/L). GG restores the cAMP/PKA pathway, a natural cholesterol synthesis pathway that generates steroid hormones, including testosterone.    

This makes GG potentially beneficial for those experiencing initial deficiencies due to age-related decline, late-onset hypogonadism, or medication-induced suppression (like statin users), as shown by preliminary research.   

Contemplating GG supplementation? While the existing research showcases promising aspects for its use as a natural approach, any decision to incorporate geranylgeraniol supplements should be made considering individual and population-based differences in testosterone levels, always in consultation with a healthcare professional.  

As we wrap up our comprehensive look at testosterone, let's recap the most important points to remember about this crucial hormone and how to maintain healthy levels naturally.  

Also Read: Breaking barriers: The Impact of Geranylgeraniol on Testosterone Levels

Do Testosterone Boosters Work? 

The honest answer: the research is still growing. Some ingredients have solid studies behind them, some look promising but need more research, and a lot depends on your starting point, like whether you're low in a nutrient to begin with. 

Zinc and vitamin D show the most consistent support when levels are low, ashwagandha and GG are promising but still emerging, while others like tribulus are studied more for libido than testosterone. Wellness Extract recommends talking to your doctor before starting any booster.  

Who shouldn’t Take Testosterone? 

You should not take testosterone if you 

Conclusion 

Understanding the hormone's complex role in your body can help you make informed choices about your health and wellness. Testosterone shapes your muscle mass, bone strength, mood, energy, and sexual health in both men and women. The goal isn't a higher number, but a healthy balance. Sleep well, train with resistance, eat enough healthy fats, and manage stress. And if you're exploring natural support for healthy testosterone levels, explore our curated range of supplements featuring natural, plant-based ingredients like geranylgeraniol to boost your testosterone levels naturally. 

FAQs 

Q1. At what age is testosterone highest? 

Testosterone levels generally peak during the late teens to early 20s in men. After around age 30, levels may gradually decline, although the rate varies from person to person. 

Q2. Is testosterone a happy hormone? 

Not exactly. Testosterone isn't a happiness hormone, but it does play a role in mood, motivation, and energy levels. Low testosterone may be linked to fatigue, irritability, and low mood. 

Q3. Can a man regain his testosterone? 

Yes, but it’s important to identify the underlying cause first. If low testosterone is linked to lifestyle factors, regular exercise, healthy eating, and quality sleep may help improve levels. However, if testosterone levels remain low, an underlying medical condition could be the reason. Consult your doctor for proper evaluation. 

Q4. What are the signs of high testosterone? 

High testosterone may cause acne, oily skin, hair loss, and mood changes. In men, it may lead to reduced sperm count, while women may experience irregular periods, excess facial hair, and difficulty getting pregnant.