SECULAR DECLINE IN TESTOSTERONE LEVELS IN HEALTHY MEN: EVIDENCE AND POTENTIAL EFFECTS OF PHYSICAL ACTIVITY, DIET, AND ENDOCRINE DISRUPTORS (2021–2026)
DOI:
https://doi.org/10.31435/ijitss.2(50).2026.6191Keywords:
Testosterone, Secular Decline, Men, Lifestyle Factors, Obesity, Diet, Physical Activity, Sleep, Endocrine Disruptors, Environmental ExposureAbstract
Background. Adequate testosterone levels are essential for maintaining physical, metabolic, and mental health. We are currently facing a problem related to a widespread decline in testosterone levels among healthy men, which has been observed across generations.
Aim. The aim of this article is to review the literature from 2021 to 2026 that reports on factors that may lower total testosterone levels in healthy men, as well as which of these factors can play a crucial role.
Material and methods. A review of the literature was conducted using the PubMed and Google Scholar databases. Meta-analyses and systematic reviews published between 2021 and 2026 were included in the analysis.
Results. Among the reviewed factors, obesity, sedentary behaviour, sleep disorders, reduced physical activity, alcohol overconsumption, and endocrine disruptors demonstrated the most consistent association with lower testosterone levels. Disruptions in the gut microbiota and diet are also likely to contribute to the secular decline in testosterone levels. Radio waves, COVID-19 and pornography have no significant impact on the decline in testosterone levels, or their influence remains unclear.
Conclusions. The secular decline in testosterone levels among healthy men appears to be a multifactorial phenomenon associated mainly with modern lifestyle, metabolic disturbances, and environmental exposures. Importantly, much of the current evidence is based on acute or observational data, limiting causal interpretation. Further long-term studies are needed to determine the relative contribution of individual factors to the population-wide decline in testosterone concentrations.
References
Nassar, G. N., & Leslie, S. W. (2026). Physiology, testosterone. In StatPearls. StatPearls Publishing.
Ide, H. (2023). The impact of testosterone in men’s health. Endocrine Journal, 70(7), 655–662. https://doi.org/10.1507/endocrj.EJ22-0604
Zhu, A., Andino, J., Daignault-Newton, S., Chopra, Z., Sarma, A., & Dupree, J. M. (2022). What is a normal testosterone level for young men? Rethinking the 300 ng/dL cutoff for testosterone deficiency in men 20–44 years old. The Journal of Urology, 208(6), 1295–1302. https://doi.org/10.1097/JU.0000000000002928
Santi, D., Spaggiari, G., Furini, C., et al. (2025). Temporal trends in serum testosterone and luteinizing hormone levels indicate an ongoing resetting of hypothalamic-pituitary-gonadal function in healthy men: A systematic review. Journal of Endocrinological Investigation, 48, 2721–2734. https://doi.org/10.1007/s40618-025-02671-9
Travison, T. G., Araujo, A. B., O’Donnell, A. B., Kupelian, V., & McKinlay, J. B. (2007). A population-level decline in serum testosterone levels in American men. The Journal of Clinical Endocrinology & Metabolism, 92(1), 196–202. https://doi.org/10.1210/jc.2006-1375
Fraile-Martínez, Ó., Ortega, M. A., & García-Montero, C. (2026). Understanding the secular decline in testosterone: Mechanisms, consequences, and clinical perspectives. International Journal of Molecular Sciences, 27(2), Article 692. https://doi.org/10.3390/ijms27020692
Mamudu, H. M., Yang, J. S., & Novotny, T. E. (2011). UN resolution on the prevention and control of non-communicable diseases: An opportunity for global action. Global Public Health, 6(4), 347–353. https://doi.org/10.1080/17441692.2011.574230
GBD 2021 Adult BMI Collaborators. (2025). Global, regional, and national prevalence of adult overweight and obesity, 1990–2021, with forecasts to 2050: A forecasting study for the Global Burden of Disease Study 2021. The Lancet, 405(10481), 813–838. https://doi.org/10.1016/S0140-6736(25)00355-1
World Health Organization. (2022). WHO European regional obesity report 2022. WHO Regional Office for Europe. https://www.who.int/europe/publications/i/item/9789289057738
Tsutsumi, T., & Tsuchiya, K. (2025). Testosterone and obesity in an aging society. Biomolecules, 15(11), Article 1521. https://doi.org/10.3390/biom15111521
Su, L., Zhang, S. Z., Zhu, J., Wu, J., & Jiao, Y. Z. (2021). Effect of partial and total sleep deprivation on serum testosterone in healthy males: A systematic review and meta-analysis. Sleep Medicine, 88, 267–273. https://doi.org/10.1016/j.sleep.2021.10.031
Su, L., Meng, Y. H., Zhang, S. Z., Cao, Y., Zhu, J., Qu, H., & Jiao, Y. Z. (2022). Association between obstructive sleep apnea and male serum testosterone: A systematic review and meta-analysis. Andrology, 10(2), 223–231. https://doi.org/10.1111/andr.13111
Wang, H., Lu, J., Xu, L., Yang, Y., Meng, Y., Li, Y., & Liu, B. (2023). Obstructive sleep apnea and serum total testosterone: A systematic review and meta-analysis. Sleep and Breathing, 27(3), 789–797. https://doi.org/10.1007/s11325-022-02655-6
Domes, G., Linnig, K., & von Dawans, B. (2024). Gonads under stress: A systematic review and meta-analysis on the effects of acute psychosocial stress on gonadal steroid secretion in humans. Psychoneuroendocrinology, 164, Article 107004. https://doi.org/10.1016/j.psyneuen.2024.107004
Tu, Q., Li, G., & Wang, S. (2026). Effect of acute exercise on the dynamics of testosterone levels: A systematic review of randomized controlled trials. PeerJ, 14, Article e20615. https://doi.org/10.7717/peerj.20615
Mennitti, C., Farina, G., Imperatore, A., De Fonzo, G., Gentile, A., La Civita, E., Carbone, G., De Simone, R. R., Di Iorio, M. R., Tinto, N., Frisso, G., D’Argenio, V., Lombardo, B., Terracciano, D., Crescioli, C., & Scudiero, O. (2024). How does physical activity modulate hormone responses? Biomolecules, 14(11), Article 1418. https://doi.org/10.3390/biom14111418
Coates, A. M., Joyner, M. J., Little, J. P., Jones, A. M., & Gibala, M. J. (2023). A perspective on high-intensity interval training for performance and health. Sports Medicine, 53(Suppl. 1), 85–96. https://doi.org/10.1007/s40279-023-01938-6
Danković, G., Lazić, A., Andrieieva, O., Korobeinikov, G., Stanković, D., & Trajković, N. (2025). Effects of high-intensity interval training on physical fitness and body composition in recreationally active females: A systematic review and meta-analysis. Scientific Reports, 15(1), Article 33982. https://doi.org/10.1038/s41598-025-11809-x
Qi, K., Tan, L., Xu, Q., Xu, Y., Kawczyński, A., & Chen, A. (2026). Effects of high-intensity interval training on aerobic capacity and athletic performance in trained athletes: A systematic review and meta-analysis. BMC Sports Science, Medicine and Rehabilitation, 18(1), Article 41. https://doi.org/10.1186/s13102-025-01479-7
Dote-Montero, M., Carneiro-Barrera, A., Martinez-Vizcaino, V., Ruiz, J. R., & Amaro-Gahete, F. J. (2021). Acute effect of HIIT on testosterone and cortisol levels in healthy individuals: A systematic review and meta-analysis. Scandinavian Journal of Medicine & Science in Sports, 31(9), 1722–1744. https://doi.org/10.1111/sms.13999
Pinto, A. J., Bergouignan, A., Dempsey, P. C., Roschel, H., Owen, N., Gualano, B., & Dunstan, D. W. (2023). Physiology of sedentary behavior. Physiological Reviews, 103(4), 2561–2622. https://doi.org/10.1152/physrev.00022.2022
Edwardson, C. L., Gorely, T., Davies, M. J., Gray, L. J., Khunti, K., Wilmot, E. G., Yates, T., & Biddle, S. J. (2012). Association of sedentary behaviour with metabolic syndrome: A meta-analysis. PLOS ONE, 7(4), Article e34916. https://doi.org/10.1371/journal.pone.0034916
Biernikiewicz, M., Rusiecka, A., & Kałka, D. (2025). Obesity and sexual desire: A systematic review and meta-analysis. The Journal of Sexual Medicine, 22(5), 677–693. https://doi.org/10.1093/jsxmed/qdaf057
Ken-Dror, G., Fluck, D., Fry, C. H., & Han, T. S. (2024). Meta-analysis and construction of simple-to-use nomograms for approximating testosterone levels gained from weight loss in obese men. Andrology, 12(2), 297–315. https://doi.org/10.1111/andr.13484
Smith, S. J., Teo, S. Y. M., Lopresti, A. L., Heritage, B., & Fairchild, T. J. (2022). Examining the effects of calorie restriction on testosterone concentrations in men: A systematic review and meta-analysis. Nutrition Reviews, 80(5), 1222–1236. https://doi.org/10.1093/nutrit/nuab072
Whittaker, J. (2023). High-protein diets and testosterone. Nutrition and Health, 29(2), 185–191. https://doi.org/10.1177/02601060221132922
Whittaker, J., & Harris, M. (2022). Low-carbohydrate diets and men’s cortisol and testosterone: Systematic review and meta-analysis. Nutrition and Health, 28(4), 543–554. https://doi.org/10.1177/02601060221083079
Whittaker, J., & Wu, K. (2021). Low-fat diets and testosterone in men: Systematic review and meta-analysis of intervention studies. The Journal of Steroid Biochemistry and Molecular Biology, 210, Article 105878. https://doi.org/10.1016/j.jsbmb.2021.105878
Furini, C., Spaggiari, G., Simoni, M., Greco, C., & Santi, D. (2023). Ketogenic state improves testosterone serum levels: Results from a systematic review and meta-analysis. Endocrine, 79(2), 273–282. https://doi.org/10.1007/s12020-022-03195-5
Ren, X., Zhang, X., Chen, X., Zhang, T., Li, G., Zhou, X., Su, S., Zhang, W., Qin, C., & Wang, S. (2021). Evaluation of post-adolescence exposure to bisphenol A on reproductive outcomes of male rodent models. Reproductive Toxicology, 101, 124–136. https://doi.org/10.1016/j.reprotox.2021.03.004
Eales, J., Bethel, A., Galloway, T., Hopkinson, P., Morrissey, K., Short, R. E., & Garside, R. (2022). Human health impacts of exposure to phthalate plasticizers: An overview of reviews. Environment International, 158, Article 106903. https://doi.org/10.1016/j.envint.2021.106903
Hamed, M. A., Akhigbe, T. M., Adeogun, A. E., Adesoye, O. B., & Akhigbe, R. E. (2023). Impact of organophosphate pesticide exposure on human semen parameters and testosterone: A systematic review and meta-analysis. Frontiers in Endocrinology, 14, Article 1227836. https://doi.org/10.3389/fendo.2023.1227836
Sang, L., Ge, Y., Liu, F., Wei, K., Shen, X., Zhang, Y., Li, Z., Lu, W., Gao, X., & Zhang, Y. (2024). Association between per- and polyfluoroalkyl substances and sex hormone levels in males based on human studies. Ecotoxicology and Environmental Safety, 271, Article 115998. https://doi.org/10.1016/j.ecoenv.2024.115998
Kuehn, B. M. (2019). Growing global alcohol use. JAMA, 322(3), 198. https://doi.org/10.1001/jama.2019.9914
Huang, D. Q., Mathurin, P., Cortez-Pinto, H., & Loomba, R. (2023). Global epidemiology of alcohol-associated cirrhosis and HCC: Trends, projections and risk factors. Nature Reviews Gastroenterology & Hepatology, 20(1), 37–49. https://doi.org/10.1038/s41575-022-00688-6
Santi, D., Cignarelli, A., Baldi, M., et al. (2024). Chronic alcohol consumption influences the gonadal axis in men: Results from a meta-analysis. Andrology, 12, 768–780. https://doi.org/10.1111/andr.13526
United Nations Office on Drugs and Crime. (2025). World drug report 2025.
Belladelli, F., Del Giudice, F., Kasman, A., Kold Jensen, T., Jørgensen, N., Salonia, A., & Eisenberg, M. L. (2021). The association between cannabis use and testicular function in men: A systematic review and meta-analysis. Andrology, 9(2), 503–510. https://doi.org/10.1111/andr.12953
Teixeira, T. A., Iori, I., Andrade, G., Saldiva, P. H. N., Drevet, J. R., Costa, E. M. F., & Hallak, J. (2022). Marijuana is associated with a hormonal imbalance among several habits related to male infertility: A retrospective study. Frontiers in Reproductive Health, 4, Article 820451. https://doi.org/10.3389/frph.2022.820451
Hansen, C. H., Larsen, L. W., Sørensen, A. M., Halling-Sørensen, B., & Styrishave, B. (2017). The six most widely used selective serotonin reuptake inhibitors decrease androgens and increase estrogens in the H295R cell line. Toxicology in Vitro, 41, 1–11. https://doi.org/10.1016/j.tiv.2017.02.001
Pavlidi, P., Kokras, N., & Dalla, C. (2021). Antidepressants’ effects on testosterone and estrogens: What do we know? European Journal of Pharmacology, 899, Article 173998. https://doi.org/10.1016/j.ejphar.2021.173998
Stedman, M., Davies, M., Levy, J. W., Ingram, J., Taylor, D., & Heald, A. (2025). National prescribing trends and cost analysis of antidepressants, anxiolytics, and hypnotics in England, 2010–2023. Human Psychopharmacology: Clinical and Experimental, 40(5), Article e70011. https://doi.org/10.1002/hup.70011
Glina, F. P. A., Lopes, L., E Silva, R. S., Barros, E. A. C., Biselli, B., & Glina, S. (2024). Do statins decrease testosterone in men? Systematic review and meta-analysis. International Brazilian Journal of Urology, 50(2), 119–135. https://doi.org/10.1590/S1677-5538.IBJU.2023.0578
Kaltsas, A., Giannakodimos, I., Markou, E., Stavropoulos, M., Deligiannis, D., Kratiras, Z., & Chrisofos, M. (2025). The androbactome and the gut microbiota-testis axis: A narrative review of emerging insights into male fertility. International Journal of Molecular Sciences, 26(13), Article 6211. https://doi.org/10.3390/ijms26136211
Jandhyala, S. M., Talukdar, R., Subramanyam, C., Vuyyuru, H., Sasikala, M., & Nageshwar Reddy, D. (2015). Role of the normal gut microbiota. World Journal of Gastroenterology, 21(29), 8787–8803. https://doi.org/10.3748/wjg.v21.i29.8787
Kaltsas, A., Zachariou, A., Markou, E., Dimitriadis, F., Sofikitis, N., & Pournaras, S. (2023). Microbial dysbiosis and male infertility: Understanding the impact and exploring therapeutic interventions. Journal of Personalized Medicine, 13(10), Article 1491. https://doi.org/10.3390/jpm13101491
Pakpahan, C., Laurus, G., Hartanto, M. C., Singh, R., Saharan, A., Darmadi, D., Rezano, A., & Wasian, G. (2025). Potential relationship of the gut microbiome with testosterone level in men: A systematic review. PeerJ, 13, Article e19289. https://doi.org/10.7717/peerj.19289
Matsushita, M., Fujita, K., Motooka, D., Hatano, K., Hata, J., Nishimoto, M., Banno, E., Takezawa, K., Fukuhara, S., Kiuchi, H., Pan, Y., Takao, T., Tsujimura, A., Yachida, S., Nakamura, S., Obara, W., Uemura, H., & Nonomura, N. (2022). Firmicutes in gut microbiota correlate with blood testosterone levels in elderly men. The World Journal of Men’s Health, 40(3), 517–525. https://doi.org/10.5534/wjmh.210190
Liu, S., Cao, R., Liu, L., Lv, Y., Qi, X., Yuan, Z., Fan, X., Yu, C., & Guan, Q. (2022). Correlation between gut microbiota and testosterone in male patients with type 2 diabetes mellitus. Frontiers in Endocrinology, 13, Article 836485. https://doi.org/10.3389/fendo.2022.836485
Maluin, S. M., Osman, K., Jaffar, F. H. F., & Ibrahim, S. F. (2021). Effect of radiation emitted by wireless devices on male reproductive hormones: A systematic review. Frontiers in Physiology, 12, Article 732420. https://doi.org/10.3389/fphys.2021.732420
Cui, Z., Mo, M., Chen, Q., Wang, X., Yang, H., Zhou, N., Sun, L., Liu, J., Ao, L., & Cao, J. (2021). Pornography use could lead to addiction and was associated with reproductive hormone levels and semen quality: A report from the MARHCS study in China. Frontiers in Endocrinology, 12, Article 736384. https://doi.org/10.3389/fendo.2021.736384
Burkardt, T. M., Stark, R., Stalder, T., Wolf, O. T., Klucken, T., Brand, M., & Müller, S. M. (2026). Hair testosterone and cortisol interactively predict problematic pornography use in a male sample. Journal of Behavioral Addictions, 15(1), 459–470. https://doi.org/10.1556/2006.2025.00489
Chen, L., Huang, X., Yi, Z., Deng, Q., Jiang, N., Feng, C., Zhou, Q., Sun, B., Chen, W., & Guo, R. (2021). Ultrasound imaging findings of acute testicular infection in patients with coronavirus disease 2019: A single-center-based study in Wuhan, China. Journal of Ultrasound in Medicine, 40(9), 1787–1794. https://doi.org/10.1002/jum.15558
Cannarella, R., Marino, M., Crafa, A., Bagnara, V., La Vignera, S., Condorelli, R. A., & Calogero, A. E. (2024). Impact of COVID-19 on testicular function: A systematic review and meta-analysis. Endocrine, 85(1), 44–66. https://doi.org/10.1007/s12020-024-03705-7
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Copyright (c) 2026 Gracjan Rudziński, Paweł Szymonek, Rafał Gołacki, Radosław Januszczak, Karolina Szymonek, Julianna Cholewa, Bartosz Burda, Katarzyna Gołacka, Ewa Bąkowska, Bartosz Kwiatek
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