Does Red Light Therapy Increase Testosterone?
Squatting naked in front of a panel of red lights. This is what my life has come to. I set out to answer a simple question: can red light therapy increase testosterone? For 3 months, I used a red light therapy box daily and tested my blood testosterone levels before and after. Here’s what happened.
The Science Behind Red Light Therapy
Red light therapy has a plausible mechanism for increasing testosterone. Light is biologically active, and different wavelengths have different impacts on the body. Most of us are deficient in the red light spectrum. The improvements you see in health and performance generally come down to increased mitochondrial function, reduced oxidative stress from mitochondrial melatonin, and a reduction in cell cytoplasm viscosity.
Your body mounts a low-level inflammatory response to red light exposure, which makes you better at dealing with cellular stresses in the future. The theory is that by improving mitochondrial function of Leydig cells (the testosterone-producing cells in the testicles), you can increase testosterone. Hence, the slightly awkward protocol of shining red light therapy on your ball sack.
Red light therapy acts as an exercise mimetic. It produces oxidative stress where the same mechanisms that exercise produces will result from exposing your body to red light.
Why I Tested This
I’m drug-free and already training hard. Any opportunity to naturally improve body composition matters. We’re also dealing with environmental estrogens that impact body composition, making gains harder. The evidence for red light therapy generally is strong, but the evidence for testosterone specifically is scanty. There are rat studies, but not much human data. I decided to do an N equals 1 test on myself.
I’ve already shown that lifestyle tweaks can impact hormone levels. When I eliminated environmental estrogens, I took my testosterone from below the normal range for a 70-year-old man into the normal range. So it’s worth investigating.
My Testing Protocol
Five times per week, 8 to 10 minutes at a time, squatting in front of the red light box. I did blood tests at 9:00 a.m. in similar circumstances before and after the 3-month period. I tried to hold lifestyle variables constant: activity levels stayed the same, training remained roughly the same, and I was in a planned weight gain phase. It’s not a controlled trial with thousands of variables, but it’s enough for a rough indication.
The Results
Testosterone, free testosterone, and sex hormone binding globulin pretty much went from normal to normal. The very slight changes you see are nothing to write home about. It’s a very unexciting experiment. Vitamin D and cholesterol levels were also much the same. I didn’t do a full blood count, but looking at the rest of the results, I think it’s unlikely to have changed.
I’m kind of relieved rather than disappointed that there wasn’t a massive change. It highlights that there was no major deficiency, but also that if it did push me way over the normal limit, I’d be concerned about the power of this intervention.
Subjective Changes: None
Aggression, sex drive, morning wood, vascularity, muscle gain, body hair, voice – nothing noticeable. My body hair possibly grew a bit faster, but there are other mechanisms for why that would happen beyond testosterone. I wouldn’t attribute that to red light therapy.
My Conclusion
Will I stop using red light therapy? No. The evidence on red light therapy is solid and the multi-system mechanisms are fantastic. Just because it didn’t improve my testosterone isn’t something I’m bothered about. My testosterone went from normal to normal, which is fine. But because of the broad benefits of red light therapy across multiple body systems, I’ll continue using it.
I haven’t debunked the testosterone hypothesis. It just didn’t do anything for me. I’m still watching the data as it comes out. There are different dosages and different wavelengths, and we might see more compelling evidence in the future.
If You Want to Try This
Don’t buy cheap red light boxes. You could be wasting money and time. Go with quality devices from trusted manufacturers. If you do want to run your own testosterone trial, you could do blood tests and add subjective measures like erectile frequency, libido, testicular volume, and semen volume if you want to get full nerd on it. But I’m not convinced there’d be much difference.
Red light therapy is still great. I’m keeping an eye on the emerging data as new studies come out.