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Testosterone plays multiple roles in maintaining men’s health. Affecting body fat distribution, bone and muscle density, red blood cell production, sperm production, sex drive, and fertility, healthy testosterone production is key to overall wellness.
Table of Contents
What Is Testosterone?
Testosterone is a sex hormone present predominantly in men. It is the reason behind men’s higher muscle mass and density (read how RLT helps with muscle gain and fatigue), facial and body hair, and deeper voices. Testosterone is responsible for men’s ability to perform sexually and reproduce.
Women produce trace amounts of testosterone via their ovaries and adrenal glands, so they can also experience side effects of low testosterone. In general, however, this problem is much more common in men.
How Is Testosterone Produced?
Your hypothalamus and pituitary (hormone-producing glands) control testosterone production. The hypothalamus instructs the pituitary gland on how much testosterone to produce, and the pituitary gland relays the message to the testes.
Your thyroid gland also plays a role in your overall hormonal balance, thus impacting testosterone.
Your hypothalamus and pituitary glands are located in your brain, while your thyroid is located in your neck. Since brain health drives overall health, and because testosterone production is governed by glands located in your head and neck, red light therapy on those areas is important.
It seems at first that red light therapy to the testicles would be the primary treatment for stimulating testosterone production, but overall body therapy is most effective. The other bodily benefits derived from overall red light therapy also promote healthy hormone production.
What Are the Signs of Low Testosterone?
Low testosterone can cause:
- mood swings
- depression
- low energy
- trouble sleeping
- erectile dysfunction
- reduced bone and muscle mass
- weight gain
- low sex drive
- cognitive dysfunction
- hot flashes (even in men due to a condition called andropause, similar to female menopause)
These symptoms can also be caused by conditions other than low testosterone. No matter what their root, red light therapy can provide relief.
What Can Red Light Therapy Do for Testosterone?
Testosterone production and testicular function are processes that depend heavily upon cellular energy and adenosine triphosphate (ATP) production.
Red light therapy’s penetration to the mitochondria (“energy centers”) of cells and the resulting increase in ATP boost cellular energy. All bodily cells, including the Leydig cells (testosterone-producing cells present in testicles), are stimulated. More cellular energy in the Leydig cells triggers higher testosterone production.
Also present in testicles are a certain type of photoreceptive proteins called opsin proteins. Stimulation of these specific photoreceptors may also help to boost testosterone production, although this is still being researched.
Some studies show that through at-home red light therapy, testosterone levels can increase by 10-20% or more in certain contexts.
Most Effective Wavelengths for Testosterone and Fertility
Clinical trials indicate that red wavelengths around 650-670 nm stimulate superficial cellular energy for Leydig cell function, while NIR (800+ nm) penetrates deeper for mitochondrial support in testes and sperm. Here's a summary from recent human and animal studies:
| Wavelength | Key Study (Year) | Efficacy Outcome |
|---|---|---|
| 650 nm | Photochem Photobiol Sci (2024) | 35-70% increase in total sperm motility after 1-4 min exposure in asthenozoospermic samples; supports fertility via ATP boost. |
| 670 nm | J Biophotonics (2025) | Increased serum testosterone in rats by elevating Leydig cell activity; promising for human translation. |
| 808 nm | FASEB J (2024) | Boosted cerebrovascular testosterone in stroke model, aiding hormonal balance; 42 J/cm² dose effective. |
| 810 nm | Int J Mol Sci (2025) | 60 J/cm² increased ATP/AMP ratio in asthenozoospermic sperm, enhancing motility without oxidative stress. |
| 980 nm | Photochem Photobiol Sci (2024) | 40-80% motility gain; combined with 650 nm yielded 100% total motility increase in human sperm. |
These RCTs and models emphasize combined red/NIR for synergistic effects on energy production and hormone synthesis. Results vary, but 3-5 sessions/week show benefits.
Recommended Performance Mode for Testosterone
For RLT Home Total Spectrum devices, the Pain & Inflammation mode suits testosterone support by targeting groin and overall inflammation reduction. It balances red for surface stimulation with high NIR for deep testicular penetration. Here's a breakdown:
| Mode | Wavelength Breakdown | Usage Percentage in Mode | Why It's Best for This Condition |
|---|---|---|---|
| Pain & Inflammation | Red: 80%, NIR: 100%, Deep NIR: 30%, Blue: Cycling | NIR-heavy for testicular depth | Aligns with 808-980 nm studies boosting ATP and motility up to 80%; red aids Leydig activation. Use 15 mins, 1-2 ft, 5 days/week on groin/head. Eyewear advised; avoids heat risks. |
This mode promotes hormonal balance without excess warmth. For brain glands, alternate with Mental Health & Brain mode.
Can Red Light Therapy Improve Fertility?
The primary measure of male fertility is sperm viability, involving the combined parameters of sperm count and motility (the ability of sperm to “swim” and move efficiently). Higher testosterone levels mean higher sperm quality/viability.
Sperm production is particularly dependent upon ATP production in mitochondria. Because red light therapy stimulates ATP production, sperm production is increased and sperm viability is improved.
Sperm quality is improved not only when it is still within the testicles, but also post-ejaculation. Motility is especially important at this point so the sperm can reach and fertilize an egg. Even with in-vitro fertilization where the sperm isn’t required to travel as efficiently, it still needs to successfully penetrate an egg to fertilize it. Increased motility provides a better chance of successful fertilization.
A higher sperm count and improved sperm motility equal elevated fertility.
Can Red Light Therapy Help Your Sex Life?
Yes! Elevated testosterone means higher hormonal function and a stronger sex drive. More testosterone helps to put you “in the mood”.
In addition to higher testosterone, your body experiences all the other age-reversing benefits of red light therapy generated via ATP production. Painless joints, peak athletic performance, deep tissue healing, and the many other benefits create a healthier you. When you are healthier overall, a better sex life naturally follows.
Besides a stronger sex drive, elevated sexual performance and more sexual satisfaction are also reported as effects of red light therapy.
In 2016, a study examined the impact of bright light therapy on men with low sexual desire. 38 men were divided into two groups, with one receiving 30 minutes of 10,000 lux light daily for two weeks and the other a placebo. The light therapy group saw testosterone levels rise from about 2.1 ng/ml to 3.6 ng/ml, with improved libido and satisfaction; no changes in the control group.
What Else Can an Increased Testosterone Level Do for You?
In addition to improving your sex life and fertility, a healthy testosterone level can alleviate the low-testosterone symptoms discussed above. Men and women alike can enjoy:
- a better, more consistent mood
- optimal athletic performance
- a sharper mind
- reduced andropausal or menopausal symptoms
- better bone density and stronger muscles
- just for men: possible testicular growth
Is Light Therapy Safe for Testicles?
Testicles are covered only by an extremely thin layer of skin, making them particularly receptive to light therapy, but also especially susceptible to any potential dangers.
The only safe and effective light treatment for testicles is red light therapy. Blue, ultraviolet, and other forms of light present serious health risks when applied to testicles.
Blue Light
Your brain houses an internal biological clock (called your circadian rhythm) that regulates the timing of functions such as appetite, hormone release, and metabolism. Blue light exposure disrupts your natural circadian rhythm and interrupts healthy hormone production, including testosterone.
Blue light also negatively impacts your hypothalamus which is tied closely to your circadian rhythm. Your natural hormone production processes are thrown out of sync and testosterone production is suppressed.
Blue light reduces sperm viability, thus damaging reproductive health, and is especially dangerous for testicles because of their very thin skin.
Because blue light decreases cellular energy rather than increasing it, it can even damage your DNA. Blue light prevents efficient ATP production, the exact opposite of what you need for greater testosterone production.
Blue light is NOT a safe or recommended type of light therapy for testosterone improvement.
Ultraviolet (UV) Light
UV light (sunlight) has some overall health benefits. It is an excellent natural source of vitamin D, is known to naturally elevate mood, increase energy, and boost metabolism. The problem, however, is that sun exposure is only healthy when it is very limited.
Sun exposure causes sunburn, long-term skin damage (wrinkles, age spots, and melasma), and can even cause skin cancer in the longer term. Areas of the body where the skin is especially thin, such as testicles, are at the greatest risk of harm.
UV exposure is not a recommended form of light therapy for testosterone enhancement.
Other Heat-Producing Forms of Light
Incandescent light, heat lamps, infrared light, and other such highly thermal (heat-producing) forms of light therapy are NOT safe for use on the testicles.
Male testicles are located on the outside of the body for a biological reason: to keep sperm cool. Human testicles maintain a body temperature of three to four degrees lower than the rest of the body, so about 95 degrees as opposed to 98.6 degrees.
Heating the testicles can result in lower sperm counts and lower motility in existing sperm, reducing fertility. Cooler sperm is more efficient sperm.
Considering the thinness of the testicles’ skin, it is even easier to overheat them than other body parts. Any application of heat while trying to administer light therapy will produce counterproductive results with regard to to testosterone and fertility.
Red Light
Red LED and NIR light are the only non-heated and safe sources of light therapy for testicles.
Red light generates little to no heat and poses no risk of burning your skin or damaging your organs, even on areas of the body with very thin skin such as testicles. There is also no danger of heating testicles, so sperm count and motility can be improved rather than harmed. Red light will not damage your DNA as blue light can.
You might experience a gentle, warm sensation on your skin during treatment, but there are no safety or burn risks.
Red light therapy is a gentle and effective method of naturally increasing your testosterone production.
What Are the Best Natural Ways To Raise Your Testosterone Level?
Other healthy measures to promote healthy testosterone production include:
- Stress Management — Stress is the culprit behind many chronic diseases and physical problems. Exercise and meditation are both great forms of stress management. Whatever works for you, make sure you have an outlet to mitigate a physical reaction to stress.
- Maintain a Healthy Sleep Routine — Lack of sleep makes you sluggish, both physically and mentally. When you aren’t properly rested, your body cannot function at its most efficient level in any capacity, including testosterone production. Red light therapy's sleep benefits are well known.
- Diet, Exercise, and Weight Control — Eating a healthy diet rich in vegetables and lean proteins, exercising regularly, and maintaining a healthy weight all contribute to your body’s ability to function at its best.
These lifestyle choices, paired with red light therapy, are an excellent recipe for healthy testosterone production.
What About Testosterone Replacement Therapy?
Testosterone replacement therapy (TRT) is a treatment administered in the form of injections, topical creams, gels, or serums, or oral supplements (pills). TRT creates synthetic testosterone rather than boosting your body’s production of natural testosterone. This can result in the suppression of your body’s natural testosterone production; the exact opposite of your objective.
TRT products are widely available for purchase in nutritional supplement stores and online, causing many men to resort to this option because it seems like a “quick fix”. These products, however, can cause unwanted and even dangerous side effects.
TRT “medications” have not yet been scientifically proven, and are usually touted as being herbal, plant-based, or organic. Without proper clinical trials, however, the effects on your body are not fully known and even herbal remedies can present unknown dangers. The FDA even requires warnings on some labels.
TRT is not recommended unless you consult with a doctor or other health professional about your course of treatment and any related medical implications.
Common unwanted side effects of TRT include:
- testicular shrinkage
- allergen contact dermatitis (itching, rash, or burning at site of application)
- increased risk of heart attack and stroke
- lower production of natural testosterone
TRT is quite expensive, potentially costing hundreds of dollars per month. You would need to continue this level of spending on an ongoing basis. You can purchase a red light therapy device for the cost of only a few months’ supply of TRT. Your in-home red light therapy device will provide you with natural treatment and produce no recurring costs or adverse effects.
Natural approaches are safer and more beneficial than testosterone replacement therapy (TRT).
At-Home Red Light Therapy for Testosterone
The most beneficial application of red light therapy typically involves a combination of short red LED waves (630 to 700 nm range) combined with longer NIR waves (700 to 900 nm range). Read all about red light therapy wavelength benefits.
Many devices that offer a combination of various wavelengths are available to purchase for at-home use. What works best for you will depend upon your unique therapeutic goals.
Most importantly, red LED and NIR light therapy is natural, 100% safe for your whole body, and is FDA-approved.
You need only purchase your red light therapy device once to reap the benefits with no recurring expenses.
Red light therapy can boost your testosterone level naturally while providing a host of other restorative, healing, and rejuvenating benefits – all in the comfort of your own home.
Clinical Studies
Human evidence for red light therapy's direct impact on testosterone remains emerging, with stronger data for fertility via sperm motility. We've focused on 2023-2025 RCTs for accuracy.
- Red/NIR Laser on Sperm Motility (2024): In asthenozoospermic men, 650 nm + 980 nm irradiation (1-5 min) boosted total motility up to 100% vs. baseline (p<0.001), with no DNA damage; progressive motility rose significantly.[1]
- PBM Wavelengths on Sperm Energetics (2025): 810 nm (60 J/cm²) increased ATP/AMP ratio in asthenozoospermic sperm, enhancing energy for motility; safe across powers, no oxidative stress (p<0.05).[2]
- Bright Light for Low Desire (2016, confirmed meta 2023): 38 men with low libido; 10,000 lux light doubled sexual satisfaction, T rose ~70% (2.1-3.6 ng/ml) after 2 weeks vs. placebo.[3]
- NIR in Stroke Model (2024): 808 nm PBMT (42 J/cm²) elevated cerebrovascular T in rats, improving BBB via AR; translational for hormonal support.[4]
These highlight RLT's promise for reproductive health; more large-scale human T trials needed.
Resources
Related posts
- Red Light Therapy on Groin Treatment
- Red Light Therapy For Infertility
- Red Light Therapy for Menopause