Testosterone: What It Is and How It Affects Your Health

So, how much do you really know about 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, it is much more than a symbol of masculinity. 

Testosterone and its synthetic analogs have been a part of several sports doping controversies, garnering significant attention, with sportspersons using it to gain unfair competitive advantages in strength and recovery. Lately, aggressive testosterone replacement therapy (TRT) marketing has raised concerns as clinics increasingly prescribe it regardless of genuine hormone deficiencies, while TRT comes with its own set of problems. 

In the light of the above controversies, there has been a surge of interest in natural ways to support healthy testosterone levels, with new research highlighting supplements like geranylgeraniol (GG).  

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.  

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 sexes require it for healthy physiological functioning. 

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  

• Men (aged 18-39 years): 8.4-28.8nmol/L  

• Women (during reproductive age): 0.52-1.59nmol/L

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

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  

1] Sexual Function and Reproductive Health  

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

• Libido (sexual desire) 

• Erectile function in men 

• Reproductive health 

• Sperm production in men  

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: 

• Fetal sex differentiation 

• Deepening of the voice during puberty 

• Growth of facial and body hair 

• Enlargement of the genitals (penis, prostate, and testes)  

• Pubertal growth spurts  

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: 

• Building and keeping muscle mass 

• Boosting muscle strength and power  

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: 

• Decreased bone density 

• Higher risk of fractures 

• Alterations in bone structure   

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 

•  Memory and focus  

•  Spatial skills  

•  Mood stability  

• Motivation and ambition    

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 

• Increasing iron availability 

• Stimulating erythropoietin production in the kidneys 

• Enhancing the survival of red blood cell precursors 

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. 

High Testosterone 

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

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

• Increased aggression or irritability  

• Elevated risk of benign prostatic hyperplasia (BPH), which causes urinary difficulties and prostate cancer  

• Sleep disturbances  

• Cardiovascular issues such as hypertension due to fluid retention 

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

Low Testosterone (Male hypogonadism) 

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: 

• Loss of muscle mass 

• Increased body fat 

• Decreased bone density 

• Low libido and infertility 

• Fatigue and depression   

• Decreased blood cell production 

Did you know? 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: 

• Exercise: Prioritize resistance training and high-intensity interval training (HIIT).  

• Diet: Healthy fats, such as omega-3s, are required for producing steroid hormones, including testosterone. Your diet should be rich in these. Zinc and Vitamin D are also crucial for testosterone synthesis and for luteinizing hormone(LH) regulation.

• Sleep: Quality sleep of 7 to 8 hours each night should be your goal. 

• Stress Management: Meditation, breathing exercises, or mindfulness practices can help keep your cortisol (the stress hormone) levels in check.   

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 

Key Takeaways 

• Testosterone is essential for both male and female health, influencing physical, emotional, and cognitive functions. Maintaining balanced levels is crucial for overall health. 

• Low or high levels of the hormone can cause health issues and significantly affect your well-being. 

• Lifestyle plays a crucial role in hormonal balance. Exercise, nutrition, sleep, and stress management all influence your body's hormone production. 

• Testosterone naturally declines with age; the rate and impact differ among individuals. 

• Geranylgeraniol supplementation may help support and potentially increase its levels by enhancing the body's natural production pathways. 

• Always seek professional guidance for personalized advice if you suspect any symptoms of hormonal imbalance or before starting any new supplement, especially if you are on any medication.  

Understanding the hormone's complex role in your body can help you make informed choices about your health and wellness. Explore our curated range of supplements—featuring natural, plant-based ingredients like geranylgeraniol—to boost your testosterone levels naturally.  

Disclaimer: These statements have not been assessed by the FDA. The information contained within this page is for educational purposes only. It is not intended to replace the advice or care of healthcare professionals. Additionally, large-scale human studies are required to confirm the exact mechanisms and results. 

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