How To Use Red Light Therapy for Testosterone: Don’t.

Red light therapy - also called photobiomodulation (PBM) or low-level laser therapy (LLLT) - uses wavelengths between 600 and 850 nm to stimulate cellular energy production in the mitochondria. The proposed mechanism for testosterone support involves Leydig cells in the testicles: when red or near-infrared light activates cytochrome c oxidase, ATP synthesis increases, potentially enhancing steroidogenesis — the process by which cholesterol is converted into testosterone. However, current human clinical evidence does not yet confirm that consumer red light therapy devices reliably increase testosterone levels. The strongest human study (Fagiolini et al., 2016) used a bright light box, not a photobiomodulation device, had a sample size of 38, and was not replicated at scale. Animal studies show mixed results across species and conditions.

What Is Testosterone?

Testosterone is a hormone produced primarily in the testicles in males, and in smaller amounts in the ovaries in females. It belongs to a group of hormones known as androgens, often called male hormones, though they play important roles in everyone's health.

Testosterone is essential for building and maintaining muscle mass and strength, supporting bone density, influencing fat distribution, and driving libido and reproductive health. It also plays a role in mood, energy levels, and mental clarity.

Testosterone production occurs mainly in specialized cells in the testicles called Leydig cells. These cells rely on healthy mitochondria, the energy-producing structures within cells, to function properly. (1) Research published in the Journal of Clinical Endocrinology and Metabolism has documented that testosterone levels in men have been declining over recent decades, independent of age, likely driven by lifestyle and environmental factors (2). After age 30, testosterone levels typically decline at a rate of around 1 to 2% per year, which means the search for effective, evidence-based support strategies is increasingly relevant (3). When testosterone levels are lower than normal, you might notice symptoms such as fatigue, decreased motivation, reduced muscle mass, loss of strength, increased body fat, mood changes like irritability or depression, and a lower sex drive. Low testosterone can also contribute to issues like erectile dysfunction and reduced sperm motility, both of which can affect reproductive health.

Common causes of low testosterone include aging, certain medical conditions, injuries to the testicles, chronic inflammation, chronic stress, obesity, and some medications. To determine your testosterone levels, healthcare professionals typically use a blood test, usually performed in the morning when levels are at their highest.

How to Support Healthy Testosterone Levels

Lifestyle Changes

Diet. A balanced diet rich in whole foods supports hormone production and overall well-being. Healthy fats found in avocados, olive oil, nuts, and fatty fish are essential for hormone synthesis, including testosterone. Protein from lean meats, eggs, and legumes helps build and maintain muscle mass, while complex carbohydrates from whole grains and vegetables provide sustained energy. Deficiencies in nutrients like zinc and vitamin D have been linked to lower testosterone, so including foods like shellfish, beef, eggs, and fortified dairy is important. A study published in Clinical Endocrinology found a significant association between vitamin D status and serum androgen levels in men, with lower vitamin D corresponding to lower testosterone (4). Consider having your vitamin D levels checked, as supplementation may be beneficial if your healthcare provider recommends it.

Focus on eating whole, minimally processed foods and include a source of healthy fat and protein at each meal. Aim to eat a variety of colorful fruits and vegetables to ensure you are getting a broad range of nutrients.

Exercise. Regular physical activity, especially resistance training like weightlifting, has been shown to support testosterone levels. A review published in Sports Medicine confirmed that resistance exercise acutely increases testosterone concentrations, with the effect being most pronounced during high-volume, moderate-to-high-intensity training involving large muscle groups (5). Exercise helps reduce body fat, which is important because excess fat can lead to increased conversion of testosterone to estrogen. High-intensity interval training (HIIT) is also effective for supporting hormone health.

Aim for at least 150 minutes of moderate physical activity each week and include strength training exercises two to three times per week. Choose activities you enjoy so you can stay consistent and make exercise a regular part of your routine.

Sleep. Quality sleep is crucial for hormone regulation. Research published in the Journal of the American Medical Association demonstrated that restricting sleep to 5 hours per night for one week reduced daytime testosterone levels by 10 to 15% in young healthy men (6). Most testosterone release occurs during deep sleep, so poor sleep or chronic sleep deprivation can significantly lower your levels. Adults should aim for 7 to 9 hours of sleep per night. Set a consistent sleep schedule, even on weekends, and create a relaxing bedtime routine. Limiting screen time and caffeine in the evening can make it easier to fall asleep, while keeping your bedroom cool, dark, and quiet supports the restful, uninterrupted sleep your body needs.

Stress management. Chronic stress raises levels of cortisol, a hormone that can suppress testosterone production. A study in Hormones and Behavior demonstrated the inverse relationship between cortisol and testosterone, showing that elevated cortisol levels are associated with decreased testosterone (7). Managing stress through relaxation techniques, mindfulness, physical activity, or hobbies can help keep your hormones balanced. Practice deep breathing, meditation, or yoga regularly, and make sure to take breaks throughout your day. Spending time outdoors and with loved ones can also help you maintain a sense of calm and balance.

Medical Treatments

If lifestyle changes are not enough and you are experiencing persistent symptoms of low testosterone, medical treatments may be considered. Hormone replacement therapy (HRT) is a common option, involving testosterone administered through gels, patches, injections, or pellets. Certain medications may also be prescribed to address underlying causes.

Consult a healthcare provider if you have persistent symptoms of low testosterone, before starting any supplements or over-the-counter products, to discuss the risks and benefits of hormone replacement therapy, and for regular monitoring if you begin any hormone therapy.

Natural Supplements

Some natural supplements are marketed for testosterone support, such as zinc, vitamin D, fenugreek, and ashwagandha. While some studies suggest mild benefits, the evidence is mixed, and supplements should not replace proven medical treatments or healthy lifestyle habits.

To safely incorporate supplements, talk to your healthcare provider before starting any new product, choose reputable brands, and follow recommended dosages. Remember to use supplements as a complement to, not a substitute for, healthy lifestyle habits.

Research on Red Light Therapy and Testosterone: What the Studies Actually Show

Research on Red Light Therapy and testosterone is still in its early stages, and much of the available evidence focuses on related reproductive or sexual health outcomes rather than directly on testosterone levels themselves. Here is a transparent review of the key studies, including what they found and where they fall short.

The University of Siena Pilot Study (2016)

The most frequently cited human study on light therapy and testosterone was a randomized, placebo-controlled pilot study conducted by researchers at the University of Siena in Italy, led by Professor Andrea Fagiolini. The study recruited 38 men diagnosed with hypoactive sexual desire disorder or sexual arousal disorder (8).

Participants were divided into two groups. One group received treatment with a specially adapted light box in the early morning for 30 minutes per day over two weeks. The control group received a light box adapted to emit significantly less light. After two weeks, the active light therapy group reported a significant improvement in sexual satisfaction, approximately three times higher than the placebo group (8, 9).

The active group also saw testosterone levels rise from approximately 2.1 ng/ml to 3.6 ng/ml, while the control group did not see similar increases (8).

Important context: This study used a bright light box (similar to those used for Seasonal Affective Disorder), not a Red Light Therapy device. The light was administered to the torso and chest area, not the testicles. The sample size was small (38 participants), and the researchers themselves noted that future studies would need to correlate clinical findings with testosterone measurements before and after treatment (9). The study has not been replicated in a larger trial. While the results are interesting, they do not establish that Red Light Therapy devices designed for skincare can increase testosterone.

Animal Studies on Photobiomodulation and Testosterone

Several animal studies have explored the relationship between low-level laser therapy (LLLT) and testosterone.

A 2013 study by Ahn et al. found that a 670nm diode laser was effective in increasing serum testosterone levels in rats without causing visible histopathological side effects. The researchers suggested that LLLT might be an alternative treatment modality to conventional testosterone replacement therapy (10).

A 2020 study by Hasani et al. found that photobiomodulation could improve sperm parameters and increase serum testosterone in mice that had experienced scrotal hyperthermia (11). However, these were not healthy animals: they had experienced testicular damage from heat stress, and the PBM was being tested as a restorative treatment for an induced condition.

A separate study on testicular degeneration in rams found that LLLT did not improve testosterone concentration, demonstrating that results are inconsistent across species and conditions (12).

Important context: Animal studies cannot be directly extrapolated to humans. The dosages, wavelengths, treatment durations, and delivery methods used in these studies differ significantly from consumer Red Light Therapy devices designed for skincare. No animal study has established a protocol that is applicable to at-home skincare devices.

Studies on Sperm Motility and Reproductive Health

The most robust area of LLLT/PBM research related to male reproductive health involves sperm motility, not testosterone directly.

A comprehensive 2018 review published in Biomedical Research concluded that LLLT can significantly improve the survival, motility, and speed of movement of spermatozoa (13). Multiple studies have confirmed that red light at wavelengths around 630 to 650nm can increase sperm motility in men with asthenozoospermia (14, 15).

A 2017 study published in Scientific Reports found that red light improved spermatozoa motility without inducing oxidative DNA damage to the sperm, confirming the safety of the approach for this specific application (16).

A 2024 systematic review published in Reproductive Sciences examined the effects of photobiomodulation across different wavelengths on sperm cell characteristics and concluded that while results are promising for sperm motility, the field still requires standardized protocols and larger clinical trials before definitive conclusions can be drawn (17).

Important context: These studies focus on sperm motility, not testosterone production. Improved sperm motility is a valuable finding for reproductive health research, but it is a separate outcome from testosterone levels. These studies also typically use laboratory-grade equipment in controlled clinical settings, not consumer skincare devices.

The Bottom Line on the Research

Overall, while some studies indicate that light therapy may have positive effects on certain aspects of male reproductive and sexual health, there is currently no strong evidence to support the claim that Red Light Therapy is an effective method to increase testosterone or treat low testosterone. The most cited human study used a bright light box, not a Red Light Therapy device. Animal studies show mixed results that cannot be directly applied to humans. And the most robust research focuses on sperm motility, not testosterone itself. More direct, large-scale, well-controlled human studies are needed to clarify any potential connection.

What Red Light Therapy Is Actually Good For

While Red Light Therapy is not a solution for testosterone concerns, it does offer meaningful, science-backed benefits for skin health and appearance. If you are interested in what Red Light Therapy can do for your skin, Solawave specializes in FDA-cleared, at-home Red Light Therapy devices designed specifically for skin rejuvenation.

The red light therapy face mask delivers four wavelengths of light therapy, including Red (630nm), Deep Red (660nm), Amber (605nm), and Near-Infrared (830nm), through 320 medical-grade LEDs in just 3 minutes per session. It is designed to visibly smooth fine lines, support firmness, and improve overall radiance with consistent use 3 to 5 times per week.

The red light therapy wand combines Red Light Therapy at 630nm with therapeutic warmth, galvanic current, and facial massage for targeted treatment of specific facial areas. For best results, pair the wand with the LightBoost Activating Serum, as the galvanic current technology requires a water-based serum to function optimally.

For the neck and chest, the Neck and Chest Pro Light Therapy Mask addresses an area frequently exposed to sun damage and often overlooked in daily skincare. For the delicate eye area, the red light therapy eye mask paired with the LightBoost Collagen Caffeine Eye Cream offers focused treatment for dark circles, puffiness, and fine lines.

Complementary skincare products like the LightBoost Face and Neck Cream and the LightBoost Niacinamide Face and Neck Serum are formulated to enhance and complement the effects of Light Therapy treatments, supporting hydration, firmness, and a balanced complexion.

At-home options like Solawave are FDA-cleared, making them safe and reliable for regular use. With more brands entering the market without FDA clearance and therefore uncertain safety protocols, choosing an FDA-cleared device provides an important layer of confidence. Many Solawave purchases may also be eligible for coverage with FSA/HSA funds.

Explore the full Solawave collection to find the right skincare devices and products for your routine.

How Red Light Therapy Is Applied to the Testicular Area

For those exploring photobiomodulation for testicular health, the application approach used in clinical research involves exposing the lower abdomen or scrotal area to red or near-infrared light at wavelengths between 630 and 850 nm. Studies have typically used sessions of 10-30 minutes, administered 3-5 times per week, at a distance that avoids heat buildup - generally 6 to 12 inches from the device. The testicles are sensitive to temperature; heat can impair sperm production, so avoiding thermal stress is important. Consumer red light therapy devices are designed for skin-surface use and operate at lower irradiance than laboratory-grade equipment used in published studies. If you are considering this application, consult a healthcare provider before beginning. Solawave devices are FDA-cleared for skincare and are not designed or validated for testicular or hormonal applications.

Conclusion

Proven testosterone management strategies like healthy lifestyle choices, proper medical care, and professional guidance remain the most effective ways to support your testosterone levels. While research on Red Light Therapy and testosterone is ongoing, there is currently no strong clinical evidence in humans that Red Light Therapy is a cure or treatment for low testosterone or any medical condition. The most cited studies involve bright light boxes (not skincare devices), animal models (not humans), or sperm motility outcomes (not testosterone levels directly). Always prioritize safe, evidence-based methods and consult with healthcare professionals to ensure the best approach for your hormone health.

For those interested in the skincare benefits of Red Light Therapy, the full range of Solawave skincare devices offers FDA-cleared, science-backed options for supporting healthier, more radiant-looking skin from the comfort of home.

Disclaimer: This article is intended for informational purposes only and should not be interpreted as medical advice or guidance. Always seek medical advice and care from a trusted healthcare professional.

Frequently Asked Questions

Can Red Light Therapy increase testosterone levels?

There is currently no strong scientific evidence in humans supporting the idea that Red Light Therapy can increase testosterone levels. The most cited study (Fagiolini et al., 2016) used a bright light box, not a Red Light Therapy device, and had a small sample size of 38 participants (8). Animal studies using low-level laser therapy have shown mixed results: a 2013 rat study found increased serum testosterone (10), while a study on rams found no improvement (12). No large-scale, well-controlled human clinical trial has established a direct, reliable link between Red Light Therapy and testosterone production. If you are concerned about your testosterone levels, consult with a healthcare provider who can recommend proven, evidence-based approaches.

Can Red Light Therapy devices be used at home for hormone health?

Many Red Light Therapy devices are designed for home use, but their safety and effectiveness for hormone health, including testosterone, have not been established by clinical research. At-home Red Light Therapy devices like those from Solawave are FDA-cleared for skincare purposes, not for hormone management. Always consult a healthcare provider before starting any new wellness routine intended to address hormone concerns.

Can Light Therapy replace traditional treatments for low testosterone?

No. Light Therapy should not replace evidence-based treatments such as hormone replacement therapy or medications prescribed by your healthcare provider. There is no scientific consensus supporting Light Therapy as a solution for hormone imbalance or testosterone deficiency. If you are experiencing symptoms of low testosterone, consult with a healthcare professional for proper evaluation and treatment.

Is there any research connecting Red Light Therapy to male reproductive health?

Yes, but the connection is primarily to sperm motility, not testosterone. A 2018 literature review concluded that LLLT can significantly improve sperm survival, motility, and speed of movement (13). Studies on men with asthenozoospermia have shown increased sperm motility after exposure to red light at 650nm (14, 15). A 2017 study confirmed that red light improved sperm motility without causing oxidative DNA damage (16). However, these findings relate to specific reproductive health outcomes, not directly to testosterone production. A 2024 systematic review in Reproductive Sciences emphasized the need for standardized protocols and larger clinical trials before definitive conclusions can be drawn

What are the most effective ways to support healthy testosterone levels?

The most well-supported approaches include maintaining a balanced diet with adequate healthy fats, protein, zinc, and vitamin D (vitamin D status has been directly associated with serum androgen levels in men) (4); engaging in regular physical activity, especially resistance training and high-intensity interval training (resistance exercise acutely increases testosterone concentrations) (5); getting 7 to 9 hours of quality sleep per night (sleep restriction of just one week reduced daytime testosterone by 10 to 15% in young men) (6); managing stress through relaxation techniques and consistent self-care habits (elevated cortisol suppresses testosterone production) (7); and consulting with a healthcare provider if symptoms persist, as medical treatments like hormone replacement therapy may be appropriate.

How do I know if I have low testosterone?

Common symptoms of low testosterone include persistent fatigue, decreased motivation, reduced muscle mass, increased body fat, mood changes, and lower sex drive. However, these symptoms can be caused by many other conditions as well. The only reliable way to confirm low testosterone is through a blood test, typically performed in the morning when levels are highest. If you suspect you have low testosterone, consult with your healthcare provider for proper testing and evaluation.

What should I look for in a Red Light Therapy device for skincare?

For skincare purposes, look for devices that are FDA-cleared, use clinically proven wavelengths (typically in the 630 to 850nm range), and come from a reputable brand with clear safety standards. The Solawave red light therapy face mask uses four wavelengths (Amber 605nm, Red 630nm, Deep Red 660nm, and Near-Infrared 830nm) through 320 medical-grade LEDs, completing a session in just 3 minutes. With more brands entering the market without FDA clearance and therefore uncertain safety protocols, choosing an FDA-cleared device matters.

Can exercise and diet really make a difference in testosterone levels?

Yes. Lifestyle factors have a well-documented impact on testosterone levels. Regular resistance training and high-intensity exercise have been shown to support healthy testosterone production. A nutrient-rich diet that includes adequate healthy fats, zinc, and vitamin D supports hormone synthesis. Maintaining a healthy body weight is also important, as excess body fat can increase the conversion of testosterone to estrogen. These lifestyle approaches are among the most effective, evidence-based strategies for supporting hormone health.

Is Red Light Therapy safe even if it does not affect testosterone?

Yes. Red Light Therapy is generally considered safe when used as directed with an FDA-cleared device. While it is not effective for testosterone management, it does offer well-documented benefits for skin health, including supporting collagen production, reducing the appearance of fine lines and wrinkles, and improving overall skin radiance. If you are interested in these skincare benefits, explore the full range of Solawave devices.

Is red light therapy safe to use on the testicles?

Red light at 630-850 nm does not generate heat or cause oxidative DNA damage in testicular tissue, making it generally low-risk at appropriate session durations. Consumer skincare devices are not clinically validated for this application.

What wavelength of red light is used for testosterone research?

Research on testosterone and testicular health has primarily used red and near-infrared wavelengths between 630 and 850 nm. Studies have used 670 nm (Ahn 2013), 830 nm, and 808 nm, though no standardized protocol exists for human testosterone outcomes.

Sources

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2. 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. Journal of Clinical Endocrinology and Metabolism, 92(1), 196-202. https://pubmed.ncbi.nlm.nih.gov/17062768/

3. Harman, S. M., Metter, E. J., Tobin, J. D., Pearson, J., & Blackman, M. R. (2001). Longitudinal Effects of Aging on Serum Total and Free Testosterone Levels in Healthy Men. Journal of Clinical Endocrinology and Metabolism, 86(2), 724-731. https://pubmed.ncbi.nlm.nih.gov/11158037/

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7. Mehta, P. H., & Josephs, R. A. (2010). Testosterone and Cortisol Jointly Regulate Dominance: Evidence for a Dual-Hormone Hypothesis. Hormones and Behavior, 58(5), 898-906. https://pubmed.ncbi.nlm.nih.gov/20816841/

8. Fagiolini, A., et al. (2016). Bright Light Exposure Increases Testosterone Levels and Leads to Greater Sexual Satisfaction in Men with Low Sexual Desire. Presented at the European College of Neuropsychopharmacology (ECNP) Conference, Vienna, 2016. https://www.sciencedaily.com/releases/2016/09/160918214443.htm

9. Ciocca, G., Limoncin, E., Cellerino, A., Fisher, A. D., Gravina, G. L., Jannini, E. A., & Fagiolini, A. (2014). Light Therapy as a Treatment for Sexual Dysfunctions: Beyond a Pilot Study. Journal of Sexual Medicine. https://pubmed.ncbi.nlm.nih.gov/25007542/

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11. Hasani, A., Khosravi, A., Rahimi, K., et al. (2020). Photobiomodulation Restores Spermatogenesis in the Transient Scrotal Hyperthermia-Induced Mice. Life Sciences, 254, 117767. https://pubmed.ncbi.nlm.nih.gov/32407848/

12. Referenced in: Troscriptions (2025). Can Red Light Therapy Boost Testosterone Levels? Review of ram study showing LLLT did not improve testosterone concentration. https://troscriptions.com/blogs/main/red-light-therapy-and-testosterone

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14. Ban Frangez, H., Frangez, I., Verdenik, I., Jansa, V., & Virant Klun, I. (2015). Photobiomodulation with Light-Emitting Diodes Improves Sperm Motility in Men with Asthenozoospermia. Lasers in Medical Science, 30(1), 235-240. https://pubmed.ncbi.nlm.nih.gov/24854415/

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17. Comprehensive Systematic Review (2024). The Effects of Photobiomodulation Therapy in Different Light Wavelength Ranges on Sperm Cell Characteristics In Vitro and In Vivo. Reproductive Sciences. https://link.springer.com/article/10.1007/s43032-024-01657-x