Red/infrared light therapy and infrared light saunas have both gained immense popularity recently. It only takes a few minutes on social media or health blogs to get a feel for this. Many people may be wondering how they compare and whether one will replace the other. By the end of this article all the information will be provided to help answer those questions to allow the best of these technologies to be taken advantage of.
So what is red and infrared light anyway?
Let's go back to basics and refresh on this type of technology.
The electromagnetic spectrum is present all the time but isn't very obvious. The part people can see is only a small segment of it that we recognise as colour – this is called the optical window. To understand the optical window, picture a rainbow. The colours run through many shades starting with blue/purple closest to the ground, to the yellow and orange shades before the red colour on the outer edge. These shades of colours all have slightly different spectrum measurements. That red layer of the rainbow is where the red light technology lives. Now imagine there was another layer to that rainbow that can't be seen just outside the red layer. This part of the spectrum is known as infra-red. Infrared is then divided into near-, mid-, and far-infrared as it moves away from the parts of the rainbow that can be seen. Near-infrared is closest to the visible light and far-infrared is further away from the visible light.
The wavelength of red light is between 620-700 nm. Infrared wavelengths are from 700 nm to 1,100nm. The longer the wavelength within the red and infrared spectrum, the deeper it will be able to penetrate into cells. Red light has a shorter wavelength so it will only penetrate as deep as into the skin. Infrared has a longer wavelength so it is able to penetrate deeper into the body’s tissue.
What is an infrared sauna?
Heat based therapies have been around for a long time. Many cultures have used heat in many different ways, very often in a sacred place and way. The most well known, which is still the case in our modern world, is with the Finnish from Finland. They started with hot earth pits and then eventually rooms heated with wood stoves. Sauna means “earth” or “snowpit” in Finnish . Modern saunas feature heated wooden walls along with stones that are warmed by an electric heater. This creates a dry heat with temperatures around between 80ºC and 93ºC . They may also incorporate steam but not always. The sauna causes sweating and comes with many benefits.
The body function of sweating is an inbuilt cooling system. The sweat sits on the skin then evaporates which allows for cooling . Sweat isn't just water though. Sweat contains water, minerals, lactate, and urea . This varies depending on a lot of factors but something sweat does sometimes contain is toxins. So one of the benefits of sweating is detoxification.
It also appears that the heat from saunas helps to create “heat shock proteins” which are thought to protect and repair cells and improve the immune system to improve longevity . Normally these proteins occur when the body temperature increases as it would during exercise or fever from illness.
The first infrared light sauna was thought to be made in 1965 by a Japanese doctor. Instead of using the heat used in a standard sauna, infrared saunas use radiant heat coming from an infrared heat lamp. The light is directed at the body rather than heating up the room to create the dry heat . The temperature in the room using an infrared sauna is around 45ºC to 60ºC which can be more comfortable for many people . They still cause sweating to get the benefits of a traditional sauna but with less heat stress on the body. Most infrared saunas rely on light waves in the far infrared part of the spectrum. At that strength it is the only type of infrared light to be able to increase the core body temperature. An increased core temperature results in a faster heart rate and sweating .
Recently near-infrared saunas have hit the market. Due to the type of light it is, it doesn't produce the same radiant heat as far-infrared saunas. Instead they have other bulbs which do produce heat. This type of sauna does not increase the core temperature. The type of light used is also usually not strong enough to affect the body in a beneficial way.
Benefits of far-infrared sauna
* Simulates some of the benefits of exercise without doing it – beneficial for thought who are unable to exercise 
* Post exercise recovery 
* Embraces heat to improve health
* Provides a 2 in 1 therapy – heat combined with red light
* Increase endorphins 
* Stimulate the blood circulation 
* Promote relaxation/stress reduction 
* Detoxification through sweating 
* chronic illness treatment 
* Relieve pain 
* Improve mood 
* reduce risk of heart disease with reduced blood pressure 
* Alzheimer’s disease 
* Overall longevity 
* Hormone regulation 
* It is an all-over body treatment
Disadvantages to infrared saunas
* In the case of near-infrared saunas that use standard heat producing bulbs, there is a risk of burning the skin if the person gets too close or touches them. The person needs to sit at a safe distance which then makes the near-infrared light not be as beneficial.
* Waiting time for warmth to develop if it is within the home
* Only provides infrared light technology along with heat. This means when the heat is not wanted or needed, the infrared light can not be used
* Often expensive to purchase– not only is the infrared light required it usually comes set up with to make the sauna room
* If using a public one, there may be hygiene issues, unwanted social engagement or waiting times
*Can be harmful for those who are prone to dehydration, such as people with conditions such as kidney disease and on diuretic medications
* It does put a stress on the cardiovascular system so there may be a risk
* Possible electromagnetic field (EMF) exposure – some companies test for EMF or will using EMF blocking technology 
* May cause low blood pressure and/or dizziness 
* Some people can experience a slight difficulty in breathing 
* Some may experience a short term reduction in sperm count due to the heat 
* Shouldn't be used while feeling unwell, especially if a fever is being experienced 
What is red light Therapy?
Red light therapy uses near-infrared and red light wavelengths for their therapeutic and regenerative results. It is also known as photobiomodulation (PBM). Using FDA approved LED light panels and portable devices, the light is used for sessions of 10 to 15 minutes, to receive the benefits. These devices can be as compact as a torch or can be a panel of lights used for treating larger areas or the whole body.
There is no heat involved with red light therapy. The LED lights stay cool to touch. It does not cause sweating which, for people who do not like heat or have conditions where they need to avoid heat, this is a better and safer option. Red light therapy LED devices must produce powerful levels of light in order for the therapy itself to be effective.
Benefits of red light therapy
* All of the benefits of red and infrared light combined
* Does not produce heat
* It can be used before or after sporting events or at the gym
* It is hygienic
* No travelling time, waiting time or awkward social situations
* No risk of burns* It can be used if unwell or with a fever as it doesn't increase the core body temperature
* It can be used by pretty much everyone and with all health conditions (after speaking to a healthcare professional)
* Doesn't increase the heart rate or interfere with blood pressure
* Doesn't cause dehydration
* It is safe and effective
* It is very economical to purchase
* Has been proven to be beneficial in a multitude of conditions:
* Cold sores
* Foot pain
* Red light for pets
* Hair loss
* Hip pain
* Mental health
* Muscle recovery
* Peripheral neuropathy
* Wound healing
* General pain and inflammation
* Plus so much more
Disadvantages of red light therapy
* Depending on the side of the device, it may not cover a large area of the body
* It doesn't provide the benefit of the heat that far-infrared products do
* Doesn't produce the “heat shock proteins”
* Doesn't produce exercise-like reactions
So to answer the question of do they complement each other or do they compete, it can be seen that they definitely don't compete. The red light device doesn't offer all that the infrared sauna provides, just the same as the infrared sauna does not offer all the same benefits that a red light device does. They both offer benefits independently of each other. To summarise , the infrared sauna provides a whole body infrared experience combined with heat whereas the red light device offers an economical, portable and targeted therapy. In an ideal world, to have the availability of both an infrared sauna and a red light device would be the perfect solution but for many that is not viable. The best way is to compare the pros and cons of each and then decide which one is most appropriate for the current health goals.
 Brent A. Bauer, M.D., What is an infrared sauna? Does it have health benefits?, Mayo Clinic, June 2020,https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/infrared-sauna/faq-20057954
 Ruscio, Michael, MD., Infrared sauna benefits and disadvantages for your health goals, The Ruscio Institute for Functional Medicine, August, 2021,https://ruscioinstitute.com/infrared-sauna-benefits-and-disadvantages/
 Nielsen-Bobbit, J., The Ultimate Guide to Finnish Saunas, Scandinavia Standard, September, 2020,https://www.scandinaviastandard.com/the-ultimate-guide-to-finnish-saunas/
 Nave, R., Perspiration Cooling of Body, Georgia State University, Physics department, 2021,http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/sweat.html
 Sparrow, K., Sauna, Heat Shock Proteins and Longevity, Kristen Sparrow MD, May 2017,https://ksparrowmd.com/sauna-heat-shock-proteins-and-longevity/