Red light therapy is also known as Low Level Laser Therapy is used in my office as part of different sessions at no additional charge (and with your permission).

Here is what red light therapy can do (that we know about so far):

stimulates collagen production under the skin
Reduces inflammation, even arthritic inflammation
reduces muscle pain and stiffness (even in feet)
increases blood circulation to the area
has mild anti-depressant effect (like a weaker version of a full spectrum light for folks with SAD)
does NOT interfere with or interact with medications
on average, only 15-20 minutes sessions are needed
can be used as frequently as desired without any known harm

FUN FACTS!

Origin story:

It was hypothesized that light emitting diodes in the red spectrum on a specific frequency could stimulate the body into reducing inflammation where the light was focused. Naturallly, this sounded like science fiction meets new-age wishful thinking and it was put to the test to see if there was any truth to the claims. (Hurrah for scientific and medical research!)

Results:

One of the first studies they did involved volunteers who all had severe arthritis symptoms (inflammation, swelling, and pain in joints). They applied the light therapy to the affected joints for 20 +/- minutes per day without any other treatment. What they discovered was that there was a measurable reduction in arthritis symptoms after treatment, It worked! Since then, they have been experimenting with all types of conditions to see what red light therapy can and cannot do. The last article I read was about the potentials of using red light therapy trans-cranially (through the skull) for traumatic brain injury cases! If you are curious, you can do an internet search of pubmed articles and other medical research pieces and find many more studies using red light therapy.

My own testimony:

I have been witness to this myself with an 80+ year old female client who had a knee that was arthritic, the size of a large pomelo fruit and as hard as a rock. She invested in a red light therapy device for daily home use. When I saw her again less than 4 weeks later, her swollen knee had visibly reduced in size and the area around the knee was soft and pliable again like it should be. I think I was more excited about this than she was!

Recommendations for home use:

Look for something that is hands free. Trust me when I tell you that 3 minutes will seem like eternity if you are holding the device and 15 minutes will seem impossible. Also, unless you are an octopus, there is no other way to use the light on your back unless it is a hands free device.
Look for a combination of 650 nm (nanometers) and 860 or higher nm in your device. The higher the number, the deeper into the tissue the light will penetrate.
The higher nanometer will be invisible to the naked eye and will seem like the bulbs aren't working. The 650nm is used for most common applications and IS visible to the naked eye.
The light will not penetrate fabric. Make sure the skin is exposed to the light.
15-20 minutes per session is all you need but you can go reasonably longer without harm. (You also won't get much more benefit from it either.)
You want the light either at skin level or no more than 6-12 inches away from the surface of the body. If it is too far away, it weakens the effect and you will get no benefit.
This light has been shown to stimulate the thyroid. If you have a fast thyroid or you are taking thyroid medication, it is best to cover the front of your throat when using the light so that you don't end with more problems.
Looking directly into the light is not advisable. Use something to cover your eyes during treatment so that you don't accidentally damage the internal parts of your eyes.
Expensive light therapy devlces are not necessary. Find one that works with your budget and know that even smaller, flashlight size devices can be just as effective as the large wall boxes.
Remember that effects are cumulative and subtle. If you have a clearly defined issue (like my 80+ year old female client), you may find the results to be fast and dramatic. If you are not as compromised, you will still receive benefit but it may not be obvious on first applications. Be patient and think of it like teeth whitening at home. Its working but it will take more than once for it become obvious that something has changed for the better.