Erectile dysfunction (ED) is a highly common problem, affecting pretty much every man at one point or another. It has a profound effect on mood, feelings of self worth and quality of life, leading to anxiety and/or depression. Although traditionally linked to older men and health issues, ED is rapidly increasing in frequency and has become a common problem even in young men. The topic we will address in this article is whether red light can be of any use to the condition.
Erectile dysfunction basics
The causes of erectile dysfunction (ED) are numerous, with the most likely cause for an individual depending on their age. We won’t go into these in detail as they are too numerous, but it breaks down into 2 main categories:
Also known as psychological impotence. This type of neurotic social performance anxiety usually stems from previous negative experiences, forming a vicious cycle of paranoid thoughts that cancel arousal. This is the main cause of dysfunction in younger men, and for various reasons is rapidly increasing in frequency.
Various physical and hormonal issues, usually as a result of general ageing, can lead to problems down there. This was traditionally the leading cause of erectile dysfunction, affecting older men or men with metabolic issues like diabetes. Drugs like viagra have been the go-to solution.
Whatever the cause, the end result involves a lack of blood flow into the penis, a lack of retention and thus an inability to start and maintain an erection. Conventional drug treatments (viagra, cialis, etc.) are the first line of defense offered by medical professionals, but are by no means a healthy long term solution, as they will upregulate nitric oxide’s effects (aka ‘NO’ – a potential metabolic inhibitor), stimulate unnatural blood vessel growth, harm unrelated organs such as eyes, and other bad things…
Can red light help with impotence? How does the efficacy and safety compare to drug based treatments?
Erectile Dysfunction – and Red Light?
Red and infrared light therapy (from appropriate sources) is studied for a wide variety of issues, not just in humans but many animals. The following potential mechanisms of red/infrared light therapy are of particular interest to erectile dysfunction:
This is the technical term for ‘more blood flow’, due to dilation (increase in diameter) of blood vessels. The opposite is vasoconstriction.
Many researchers note that vasodilation is stimulated by light therapy (and also by various other physical, chemical and enivornmental factors – the mechanism by which the dilation comes about is different for all the different factors though – some good, some bad). The reason that improved blood flow helps erectile dysfunction is obvious, and is necessary if you want to cure ED. Red light could potentially stimulate vasodilation through these mechanisms:
Carbon Dioxide (CO2)
Commonly thought of as a metabolic waste product, carbon dioxide is actually a vasodilator, and the end result of respiration reactions in our cells. Red light supposedly acts to improve that reaction.
CO2 is one of the most potent vasodilators known to man, easily diffusing from our cells (where it is produced) into blood vessels, where it interacts almost instantly with smooth muscle tissue to cause vasodilation. CO2 plays a significant systemic, almost hormonal, role across the body, affecting everything from healing to brain function[2-5].
Improving your CO2 levels by supporting glucose metabolism (which red light, amongst other things, does) is crucial to solve ED. It also plays a more local role in areas it is produced, making direct groin and perineum light therapy of interest for ED. In fact, an increase in CO2 production can lead to a 400% increase in local blood flow.
CO2 also helps you to produce more NO, another molecule related to ED, not just at random or in excess, but just when you need it:
Mentioned above as a metabolic inhibitor, NO actually has various other effects on the body, including vasodilation[3,7]. NO is produced from arginine (an amino acid) in our diet by an enzyme called NOS. The problem with too much sustained NO (from stress/inflammation, environmental pollutants, high-arginine diets, supplements) is it can bind to respiratory enzymes in our mitochondria, preventing them from using oxygen. This poison-like effect prevents our cells from producing energy and carrying out basic functions. The main theory explaining light therapy is that red/infrared light might be able to photodissociate NO from this position, potentially allowing mitochondria to function normally again (see Fig 4.).
NO doesn’t only act as an inhibitor though, it plays a role in erection/arousal responses[8,9] (which is the mechanism exploited by drugs like viagra). ED is specifically linked to NO. Upon arousal, NO generated in the penis leads to a chain reaction. Specifically, NO reacts with guanylyl cyclase, which then increases production of cGMP. This cGMP leads to vasodilation (and thus erection) via several mechanisms. Of course, this whole process isn’t going to happen if the NO is bound to the respiratory enzymes, and so appropriately applied red light potentially shifts the NO from a harmful effect into a pro-erection effect.
Removing the NO from mitochondria, via things like red light, is also key to increasing mitochondrial CO2 production again. As mentioned above, Increased CO2 will help you produce more NO, when you need it. So it’s like a virtuous circle or a positive feedback loop. The NO was blocking aerobic respiration – once liberated, normal energy metabolism can proceed. The normal energy metabolism helps you use and produce NO at more appropiate times/areas – something key to curing ED.
As we’ve discussed in another blog post, red light used appropriately may aid in maintaining natural testosterone levels. While testosterone is actively involved in libido (and various other aspects of health), it plays a vital, direct role in erection. Low testosterone is one of the main causes of erectile dysfunction in men. Even in men with psychological impotence, an increase in testosterone levels (even if they were already in the normal range) can break the cycle of dysfunction. While endocrine problems aren’t necessarily as simple as targetting a single hormone, light therapy seems of interest in this area.
Not necessarily something you would link to ED, thyroid hormone status is actually a primary factor. In fact, bad thyroid hormone levels are detrimental to all aspects of sexual health, in men and women. Thyroid hormone stimulates metabolism in all cells of the body, in a similar way to red light, leading to improved CO2 levels (which mentioned above – is good for ED). Thyroid hormone is also the direct stimulus that the testes need to start producing testosterone. From this perspective, thyroid is a sort of master hormone, and seems to be the root cause of everything linked to physical ED. Weak thyroid = low testosterone = low CO2. Improving thyroid hormone status through diet, and even perhaps through light therapy, is one of the first things that should be attempted by men wanting to address their ED.
Another key hormone in the impotence world. High prolactin levels literally kill an erection. This is best shown by how prolactin levels skyrocket in the refractory period after orgasm, significantly reducing libido and making it hard to ‘get it up’ again. That’s just a temporary issue however – the real problem is when baseline prolactin levels rise over time due to mixture of diet and lifestyle influences. Essentially your body can be in something similar to that post-orgasmic state permanently. There are several ways to tackle long term prolactin issues, including by improving thyroid status.
Red, Infrared? What’s the best?
Going by the research, the most commonly studied lights output either red or near-infrared light – both are studied. There are several factors to consider on top of that though:
Various wavelengths have a potent effect on our cells, but there’s more to consider. Infrared light at 830nm penetrates much deeper than light at 670nm for example. The 670nm light is thought to be more likely to dissociate NO from mitochondria though, which is of particular interest for ED. Red wavelengths also showed better safety when applied to the testes, which is important here too.
What to avoid
Heat. Applying heat to genital area is not a good idea for men. Testes are extremely sensitive to heat and one of the primary functions of the scrotum is heat regulation – maintaining a temperature lower than normal body temperature. This means any source of red/infrared light that also emits a significant amount of heat will not be effective for ED. Testosterone and other measures of fertility helpful to ED will be harmed by inadvertently heating the testes.
Blue & UV. Extended exposure of blue and UV light to the genital area will have negative effects on things like testosterone and in the long-term general ED, due to the harmful interactions of these wavelengths with mitochondria. Blue light is sometimes reported as beneficial for ED. It’s worth noting that blue light is linked to mitochondrial and DNA damage in the long term, so, like viagra, probably has negative long-term effects.
Using a source of red or infrared light anywhere on the body, even unrelated areas like the back or arm for example, as a proactive anti-stress therapy for extended periods (15mins+) is something that many online have noticed beneficial effects from on ED and also morning wood. It seems that a large enough dose of light anywhere on the body, ensures molecules like CO2 produced in the local tissue enter the blood stream, leading to the beneficial effects mentioned above in other areas of the body.
- Red & Infrared light may be of interest to erectile dysfunction
- Various potential mechanisms including CO2, NO, testosterone.
- More research required to confirm.
- Red (600-700nm) seems slightly more appropriate but NIR too.
- Absolutely best range may be 655-675nm
- Do not apply heat to the genital area
Recommended light for ED
- Laser light – a new, non invasive treatment for Erectile Dysfunction: a placebo-controlled, single blinded pilot study. Y. Yacobi M.D., A. Sidi M..D. – sld.cu/galerias/pdf/sitios/rehabilitacion-fis/laser_y_disfuncion_erectil.pdf
- J Physiol, 2011. The cerebrovascular response to carbon dioxide in humans. A. Battisti-Charbonney
Reivich M. Arterial PCO2 and cerebral hemodynamics. Am J Physiol. 1964; 206: pp. 25–35.
- C Iadecola. Does nitric oxide mediate the increases in cerebral blood flow elicited by hypercapnia? Proc Natl Acad Sci U S A. 1992
- Kontos HA. Analysis of vasoactivity of local pH, PCO2 and bicarbonate on pial vessels. Stroke. 1977.
- Lohr NL. Enhancement of nitric oxide release from nitrosyl hemoglobin and nitrosyl myoglobin by red/near infrared radiation: potential role in cardioprotection. J Mol Cell Cardiol
- J Appl Physiol 1985. Joyner MJ. Nitric oxide and vasodilation in human limbs.
- Expert Opin Pharmacother. 2001 The role of nitric oxide in penile erection. Cartledge J.
- Pharmacol Ther. 2005. Nitric oxide and penile erectile function. Toda N.
- J Clin Hypertens 2006. The role of nitric oxide in erectile dysfunction: implications for medical therapy. Burnett AL.
- Carbon dioxide enhances nitration of surfactant protein A by activated alveolar macrophages. Sha Zhu. 2000.
- Erectile Dysfunction in Patients with Hyper- and Hypothyroidism: How Common and Should We Treat? GE Krassas – 2008.
- Effects of hyperthyroidism, hypothyroidism, and thyroid autoimmunity on female sexual function. A Oppo – 2011.
- Hyperprolactinemia and Erectile Dysfunction. SI Zeitlin – 2000.