Introduction: The link between testosterone levels and overall health

Testosterone plays a central role in male health across the lifespan, influencing muscle mass, bone density, libido, mood, cognition, insulin sensitivity, and cardiovascular health. From around the age of 30–40, total and free testosterone levels typically decline by approximately 1–2% per year, with a more pronounced reduction in bioavailable testosterone due to rising sex hormone‑binding globulin (SHBG). (Li, 2026)

Despite age being a natural contributor to testosterone decline, the scale of reduction observed across modern populations, amongst men from adolescence to old age is thought to be significantly influenced by lifestyle and environmental factors, including:

• Obesity and overweight: Excess adipose tissue increases aromatase activity, converting testosterone to oestrogen, and raises inflammatory cytokines that suppress the hypothalamic-pituitary-gonadal (HPG) axis, leading to lower testosterone production
• Metabolic disorders: Insulin resistance and diabetes impair Leydig cell function and disrupt the HPG axis, resulting in reduced testosterone synthesis and secretion
• Exposure to endocrine-disrupting chemicals: Phthalates, BPA, micro/nanoplastics, and pesticides interfere with androgen receptor signalling, inhibit testosterone synthesis enzymes, and disrupt hormonal feedback, contributing to lower testosterone levels
• Air and environmental pollutants: Pollutants such as heavy metals and particulate matter induce oxidative stress and inflammation, damaging testicular tissue and impairing hormone production
• Sedentary lifestyle: Physical inactivity reduces testosterone by decreasing muscle mass and metabolic rate, and by failing to stimulate the HPG axis through regular exercise
• Unhealthy diet: Diets high in processed foods, sugars, and unhealthy fats promote inflammation, oxidative stress, and micronutrient deficiencies (e.g., zinc), all of which suppress testosterone synthesis
• Sleep deprivation: Sleep disorders including sleep apnoea, circadian rhythm disruption, and poor sleep quality all contribute to testosterone suppression, creating a bidirectional relationship where low testosterone can also impair sleep quality
• Chronic stress: Chronic psychological stress elevates cortisol, which directly suppresses testosterone production and disrupts the HPG axis
• Prescribed medications: Certain medications (e.g., opioids, glucocorticoids, antidepressants) inhibit testosterone synthesis or block androgen receptors, leading to lower circulating testosterone
• Viral infections: Viral infections (including COVID-19) can damage testicular tissue, disrupt hormone signalling, and trigger systemic inflammation, all contributing to reduced testosterone
• Gut dysbiosis: Individual bacterial species are capable of directly degrading androgens, and broader gut microbiota alterations have been associated with reduced circulating testosterone levels. (Fraile-Martínez, 2026)

These factors have been linked to declines in both total and free testosterone, contributing to declines in metabolic, reproductive, and psychological health and suggest the need for integrated interventions to preserve healthy testosterone levels in men.

Male hypogonadism can provoke a cascade of changes that compromise quality of life, with common manifestations including:

• Sexual dysfunction – Loss of libido and erectile dysfunction are hallmarks of testosterone deficiency.
• Low mood and motivation – Chronic fatigue, reduced motivation, low self-confidence and depressive symptoms are commonly observed. Cognitive changes can accompany mood decline, including impaired memory, concentration, and spatial cognition, leading to a subjective feeling of mental sluggishness.
• Impaired physical composition and strength - Testosterone is a key anabolic hormone for muscle maintenance and bone density. Thus, its deficiency contributes to sarcopenia (loss of muscle mass and strength) and osteopenia/osteoporosis.
• Metabolic effects - Hypogonadism is frequently accompanied by components of the metabolic syndrome, including insulin resistance, dysglycaemia, central obesity, dyslipidaemia, and hypertension. Low testosterone and metabolic syndrome exacerbate each other in a bidirectional fashion. (Zitzmann, 2026)

Importantly, testosterone decline often occurs alongside benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS), making prostate supportive strategies clinically relevant alongside supporting testosterone levels. (O'Mahony, 2025)

Nutritional interventions that can support testosterone balance

Targeted botanical and micronutrient interventions can support testosterone balance, androgen metabolism, and prostate health, particularly where lifestyle optimisation alone is insufficient.

Saw Palmetto (Serenoa repens)

Saw palmetto is one of the most extensively researched botanicals for prostate health. Its primary mechanism relates to inhibition of 5‑α‑reductase, the enzyme responsible for converting testosterone into dihydrotestosterone (DHT), a more potent androgen strongly implicated in BPH. (Kwon, 2019)

By moderating DHT activity locally within prostate tissue, without directly suppressing systemic testosterone, saw palmetto helps alleviate urinary symptoms and supports prostate comfort.

In addition, saw palmetto exhibits anti‑inflammatory and anti‑androgen‑receptor binding effects. (Antoniou, 2023)

Clinical relevance: Particularly useful where prostate symptoms coexist with age‑related testosterone decline.

Nettle Root Extract (Urtica dioica)

Nettle root is mechanistically distinct from nettle leaf and is specifically used in male reproductive and prostate health formulations. Nettle root contains lignans and other phytochemicals that can bind to SHBG, reducing its affinity for testosterone, thereby increasing the proportion of free testosterone in circulation. (Csikós, 2021)

Nettle root can disrupt several pathways involved in the genesis of BPH. Lignans inhibit the binding of androgens to the prostate’s membrane receptors, inhibiting their proliferative activity on prostate tissues. Nettle root also demonstrates anti‑inflammatory activity within prostate tissue and may inhibit aromatase activity, contributing to a more favourable androgen‑oestrogen balance. (Bhusal, 2022)

Clinical studies have shown symptom improvement in BPH and LUTS, particularly when nettle root is combined with saw palmetto. (Csikós, 2021)

Clinical relevance: Supports bioavailable testosterone while complementing prostate focused botanicals.

Maca Root (Lepidium meyenii)

Maca is classified as an adaptogenic root with traditional use in fertility, libido, and vitality. Unlike direct androgenic agents, maca does not significantly alter serum testosterone levels, but instead appears to improve downstream outcomes such as sexual desire, sperm parameters, and mood. (Shin, 2023)

These effects are attributed to maca’s adaptogenic properties, neuroendocrine modulation, and antioxidant activity, rather than direct stimulation of testosterone production. Maca may also support sperm quality and fertility, making it a valuable ingredient for men seeking to address the functional impacts of age-related hormonal decline or suboptimal androgen status. (Ulloa Del Carpio, 2024)

Clinical relevance: Useful where testosterone related symptoms persist despite “normal” serum levels or where stress and fatigue are contributory.

Beta‑Sitosterol

Beta‑sitosterol is one of the most well-researched phytosterols for the management of BPH, demonstrating meaningful improvements to LUTS. It is thought to exert mild, local inhibition of 5‑α‑reductase and anti‑inflammatory effects within prostatic tissue, helping to reduce DHT activity, without compromising systemic testosterone status. (Macoska, 2023)

Clinical relevance: Supports prostate comfort and urinary function, whilst preserving testosterone levels.

Pumpkin Seed (Cucurbita pepo)

Pumpkin seed extracts provide zinc, phytosterols, and fatty acids that act synergistically to support prostate health. Pumpkin seed may inhibit testosterone-induced prostate growth and improve urinary symptoms, potentially via 5‑α‑reductase modulation and anti-inflammatory effects. (Theil, 2022)

While pumpkin seed does not directly stimulate testosterone production, it can exhibit a protective role by reducing testicular oxidative damage and inflammation, thereby preserving Leydig cell structure and function rather than stimulating excess androgen production. (Ajibola, 2025)

Clinical relevance: A nutrient‑dense, prostate supportive nutrient to help preserve healthy testosterone levels.

Lycopene

Lycopene is a powerful carotenoid that preferentially accumulates in androgen‑sensitive tissues, including the prostate and testes. By reducing oxidative stress and supporting endogenous antioxidant defences, lycopene helps protect these tissues from age‑related cellular damage that can disrupt prostate function and healthy testosterone signalling.

Lycopene also modulates inflammatory pathways and growth‑related signalling (including IGF‑1) mechanisms relevant to prostate enlargement and dysfunction that often accompany testosterone decline. Its high concentration in the testes further supports a role in male reproductive and hormonal health. (Shafe, 2024)

Low dietary intake of lycopene has also been associated with a higher incidence of erectile dysfunction. (Gao, 2024)

Clinical relevance: Supports long‑term prostate health and antioxidant protection within androgen‑sensitive tissues.

Zinc

Zinc is an essential trace mineral for normal testosterone synthesis and regulation, playing a critical role in the function of Leydig cells and the activity of key steroidogenic enzymes involved in androgen production. Zinc deficiency is consistently associated with reduced circulating testosterone levels, while restoring adequate zinc status supports the recovery and maintenance of normal testosterone production. Zinc is also required for the structural integrity and signalling capacity of the androgen receptor, helping tissues respond appropriately to available testosterone.

In addition to its role in hormonal regulation, zinc is highly relevant to prostate health, where it acts as a regulator of prostate cellular metabolism, oxidative balance and inflammatory signalling. Adequate zinc availability helps maintain normal prostate tissue structure and function, supports antioxidant defences, and influences pathways involved in BPH and age‑related prostate dysfunction. (Marín de Jesús, 2024)

Clinical relevance: Foundational micronutrient for testosterone production and prostate integrity.

Conclusion

Testosterone plays a central role in male metabolic, reproductive and psychological health, yet modern men are experiencing earlier and more pronounced declines driven not only by ageing, but by lifestyle, environmental and metabolic stressors. As testosterone falls, men may experience changes in energy, mood, body composition, libido and metabolic resilience, often alongside prostate enlargement and urinary symptoms. Supporting healthy testosterone levels therefore requires more than simply targeting hormone production in isolation. A comprehensive approach that addresses androgen metabolism, oxidative stress, inflammation, SHBG activity and prostate health, using targeted botanicals and essential micronutrients, offers a clinically relevant strategy to preserve hormonal balance, functional vitality and long‑term prostate integrity in men.

References

• Ajibola TA, Enye LA, et al. Ameliorative effects of pumpkin seed oil on sexual‑reproductive indices of salt‑loaded male rats: involvement of the hypothalamic‑pituitary‑gonadal axis. Pharmacol Toxicol Nat Med. 2025;5(3–4):53‑66.
• Antoniou V, Gauhar V, et al. Role of Phytotherapy in the Management of BPH: A Summary of the Literature. J Clin Med. 2023 Feb 28;12(5):1899.
• Bhusal KK, Magar SK, et al Nutritional and pharmacological importance of stinging nettle (Urtica dioica L.): A review. Heliyon. 2022 Jun 22;8(6):e09717.
• Csikós E, Horváth A, et al. On Behalf Of The Oemonom. Treatment of Benign Prostatic Hyperplasia by Natural Drugs. Molecules. 2021 Nov 25;26(23):7141.
• Fraile-Martínez Ó, Ortega MA, et al. Understanding the Secular Decline in Testosterone: Mechanisms, Consequences, and Clinical Perspectives. Int J Mol Sci. 2026 Jan 9;27(2):692.
• Gao Y, Liu C, et al. Lycopene intake and the risk of erectile dysfunction in US adults: NHANES 2001-2004. Andrology. 2024 Jan;12(1):45-55.
• Kwon Y. Use of saw palmetto (Serenoa repens) extract for benign prostatic hyperplasia. Food Sci Biotechnol. 2019 Apr 17;28(6):1599-1606.
• Li S. Testosterone deficiency in aging males: a dual threat to vascular and bone health through coronary artery calcification and osteoporosis - a narrative review. Aging Male. 2026 Dec 31;29(1):2662042.
• Macoska JA. The use of beta-sitosterol for the treatment of prostate cancer and benign prostatic hyperplasia. Am J Clin Exp Urol. 2023 Dec 15;11(6):467-480. PMID: 38148931; PMCID: PMC10749388.
• Marín de Jesús S, Vigueras-Villaseñor RM, et al. Zinc and Its Impact on the Function of the Testicle and Epididymis. Int J Mol Sci. 2024 Aug 19;25(16):8991.
• O'Mahony CJ, Arshad MA, Norton SM. Testosterone and Lower Urinary Tract Symptoms: A Narrative Review. Curr Urol Rep. 2025 Nov 28;26(1):75.
• Shafe MO, Gumede NM, et al. Lycopene: A Potent Antioxidant with Multiple Health Benefits. J Nutr Metab. 2024 Jun 8;2024:6252426.
• Shin D, Jeon SH, et al. Efficacy and Safety of Maca (Lepidium meyenii) in Patients with Symptoms of Late-Onset Hypogonadism: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. World J Mens Health. 2023 Jul;41(3):692-700.
• Theil G, Richter M, et al. Extract from Cucurbita pepo improves BPH symptoms without affecting sexual function: a 24-month noninterventional study. World J Urol. 2022 Jul;40(7):1769-1775.
• Ulloa Del Carpio N, Alvarado-Corella D, et al. Exploring the chemical and pharmacological variability of Lepidium meyenii: a comprehensive review of the effects of maca. Front Pharmacol. 2024 Feb 19;15:1360422.
• Zitzmann M, Soave A, Bier S. Functional testosterone deficiency in aging men: Clinical impact, diagnostic pathways, and treatment strategies. Maturitas. 2026 Apr;207:108870.

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