The average American spends over 90 percent of their time indoors. If you’re not getting outside in the sun regularly, your body may be craving natural light. And if you’re spending all day in front of electronic screens, you’re bombarding yourself at all hours with artificial light that can wreak havoc on your circadian rhythm. A lack of natural light and an overload of artificial blue light are bigger health risks than most people realize and can have serious physical and mental consequences—like headaches, chronic fatigue, insomnia, and depression.

The obvious solution is to simply spend more time outside during the day, but that’s often not possible for most adults. With jobs and other daily indoor obligations, most people just can’t squeeze an extra two hours of sunlight into their busy schedule.

And that doesn’t mean our bodies don’t feel the effects. Despite massive advancements in lighting technology, our bodies and biological processes are still designed to run on natural light. When we don’t get enough, our cells can struggle to produce enough energy to power our body.

Fortunately, there is a way to get more healthy light every day without spending more time in the sun, or even outdoors. It’s called light therapy, and it’s a simple solution to the light deficiency problem brought about by our modern lifestyles.

What is Light Therapy?

Light therapy—or photobiomodulation—is a noninvasive therapy that delivers natural light to your skin and cells. Not just any natural light, though. Photobiomodulation delivers only specific red and near-infrared wavelengths that have been found to be the most clinically therapeutic, without harmful UV rays, heat, or other side effects.

A quality light therapy device uses medical-grade LEDs to deliver the light to your skin and cells, where it produces all kinds of health benefits. It’s easy to set up light therapy in just about any indoor space, and the treatments require minimal effort: With something like a Joovv full-body system, you simply stand or sit in front of your device and bask in the glow of healthy light for 10 to 20 minutes a day.

The Clinically Proven Health Benefits of Light Therapy

Hundreds of peer-reviewed clinical trials and studies around the world attest to the effectiveness of light therapy. Here are four of the most widely studied benefits:

  1. Skin, Collagen, and Anti-Aging: Red light therapy feels rejuvenating for your skin, in part because it stimulates the production of collagen, which gives skin its elasticity, hair its strength, and connective tissue its ability to hold everything together. Clinical studies have found that light therapy improves skin tone and complexion, diminishes signs of aging, and speeds the healing of wounds and scars.
  2. Muscle Recovery, Growth and Strength: Light therapy helps your body produce more cellular energy and reduces oxidative stress. This allows your tired and damaged muscle tissue to repair itself and regenerate faster. Research published in the American Journal of Physical Medicine and Rehabilitation in 2016 shows that light therapy also enhances the growth of healthy muscle tissue, increasing muscle size, bulk, and strength.

In 2015, a study published in the European Journal of Applied Physiology compared muscle growth and strength between two groups of athletes—one using light therapy with exercise, the other with exercise alone. The researchers found that muscle thickness and strength were drastically improved (over 50 percent) in the athlete group who used light therapy. Results were clearly measurable using ultrasound imaging and isokinetic dynamometry.

  1. Inflammation and Joint Pain: One of the main responses to red-light therapy is a major reduction in inflammation and oxidative stress, with significantly decreased joint pain—as shown in numerous clinical trials.
  2. Melatonin and Sleep: All the time people spend indoors surrounded by bright, artificial light messes up their circadian rhythm and makes it harder to sleep. Exposure to red and near infrared does the opposite and helps protect the internal clock. Clinical studies show light therapy also increases natural melatonin production for healthier sleep.

    Research on light therapy has also found these treatments to be reliable and safe. A 2013 meta-analysis of light therapy treatments, conducted by Harvard and MIT researchers, praised its “noninvasive nature and almost complete absence of side effects.”

How Light Therapy Works

Light therapy works at the cellular level, in your mitochondria. Often called the powerhouses of the cells, the mitochondria are hard at work making adenosine triphosphate to fuel your body.

ATP is made in the mitochondria every day through the cellular respiration process, which cycles the oxygen we breathe, the water we drink, and the food we eat with the goal of producing more energy. When you’re sick, injured, stressed, or tired, your mitochondria produce excess nitric oxide, which can inadvertently bind with key enzymes during something called oxidative phosphorylation. This action eventually halts the production of ATP.

The photons in red and near-infrared light excite the electrons involved in cellular respiration, breaking up nitric oxide bonds and restoring the normal pathway for ATP production. The more efficiently your cells create ATP through cellular respiration, the better your cells function on all levels—and the better your body feels and performs.

If you want to get even deeper into the science, check out this article on how red and near-infrared light stimulates cellular respiration.

What to Look for in a Light Therapy Device

Historically, light therapy was only available in luxury spas and clinics, which isn’t a good recipe for optimal daily use. Today, you can get a quality in-home light therapy device and enjoy the health benefits with comfort and convenience. But what defines a high-quality device?

If you’re not familiar with light therapy, it can be difficult to compare devices. It doesn’t help that some manufacturers make false claims and keep their product specs in the dark. When considering different devices, start by making sure the manufacturer is transparent and trustworthy. Not sure? Ask these three key questions:

  • Are they open about their product specs, like power measurements and wavelengths? If you have to hunt that data down, it’s a bad sign.
  • Are their product specs and power measurements independently verified?
  • Have the product and production process been cleared by the FDA? If not, why?

Once you’re satisfied, the next step is to compare devices. These are the three most important factors to consider:

  1. Treatment Area Size: To experience the full range of light therapy benefits, it’s best to treat your entire body with a uniform, consistent dosage. Size matters in light therapy because you simply can’t treat the whole body or get that ideal, uniform dose from a small device. Look for a product that can cover enough treatment area to get the job done for your entire body.
  2. Total Delivered Power: Measuring the power of light is complex, and it’s nearly impossible to get accurate readings without investing in expensive diagnostic equipment. Many devices are measured in irradiance, or light power, but that’s just a start and doesn’t tell you much. Because treatment area is so vital, you have to go further and measure total light output based on the power and the total area the device covers. That’s how photobiomodulation scientists measure light therapy devices.

Harvard Medical School’s Dr. Michael Hamblin, one of the world’s leading light therapy researchers, explains: “Total light energy is the most accurate and comprehensive way to measure the power of light therapy devices and treatments. If you only account for irradiance—versus how much total energy a device delivers—you miss the larger picture of how light therapy positively benefits the person using it.”

Look for a product that delivers at least 10-15 joules/cm2 over a sizeable treatment area. Bottom line: If a manufacturer gives only an irradiance statistic and won’t provide a total delivered power metric that takes into account size of treatment area, look elsewhere.

  1. Clinically Beneficial Wavelengths: Not all wavelengths on the light spectrum are therapeutic. The red and near-infrared range of wavelengths, from approximately 600 to 950 nanometers, is known as the “therapeutic window” for light therapy, but the 700-770 nm range has very little benefit. Stick to devices offering red light in the mid-600 nm range and near infrared light in the mid-800 nm range, which have been repeatedly shown to be the most clinically effective.

More Healthy Light Means Better Health and Performance

Humans need natural light every day, and we always have. For many, our modern lifestyles and jobs keep us indoors, surrounded by artificial light at all hours. Deficiency of natural can have serious health consequences, yet not everyone can spend more hours in the sun every week.

Fortunately, even if you can’t get outside more often, you can get the natural light your body needs—and many proven health benefits—from high-quality light therapy.


  1. Klepeis N, Nelson W, Ott W, Robinson J, Tsang A, et al. “The National Human Activity Pattern Survey (NHAPS): A Resource for Assessing Exposure to Environmental Pollutants.” J Exposure Analysis Environ Epidem. 2001;11: 231-252.
  2. Hatori M, Gronfier C, Van Gelder R, Bernstein P, Carreras J, et al. “Global Rise of Potential Health Hazards Caused by Blue Light-Induced Circadian Disruption in Modern Aging Societies.” NPJ Aging Mech Dis. 2017;3:9. doi: 10.1038/s41514-017-001-2
  3. Ferraresi C, Hamblin M, Parizotto N. “Low-Level Laser (Light) Therapy (LLLT) on Muscle Tissue: Performance, Fatigue and Repair Benefited by the Power of Light.” Photonics Lasers Med. 2012 Nov 1;1(4): 267–286. doi:10.1515/plm-2012-0032
  4. Emília de Abreu Chaves M, Rodrigues de Araújo A, Piancastelli ACC, Pinotti M. “Effects of Low-Power Light Therapy on Wound Healing: LASER x LED.” An Bras Dermatol. 2014 Jul-Aug; 89(4): 616–623. doi: 10.1590/abd1806-4841.20142519
  5. de Almeida P, Lopes-Martins RA, De Marchi T, Tomazoni SS, Albertini R, et al. “Red (660 nm) and Infrared (830 nm) Low-Level Laser Therapy in Skeletal Muscle Fatigue in Humans: What Is Better?” Lasers Med Sci. 2012 Mar;27(2): 453-8. doi: 10.1007/s10103-011-0957-3
  6. Ferraresi C, Bertucci D, Schiavinato J, Reiff R, Araújo A, et al. “Effects of Light-Emitting Diode Therapy on Muscle Hypertrophy, Gene Expression, Performance, Damage, and Delayed-Onset Muscle Soreness: Case-control Study with a Pair of Identical Twins.” Am J Phys Med Rehabil. 2016 Oct;95(10): 746-57. doi: 10.1097/PHM.0000000000000490
  7. Baroni BM, Rodrigues R, Freire BB, Franke RA, Geremia JM, Vaz MA. “Effect of Low-Level Laser Therapy on Muscle Adaptation to Knee Extensor Eccentric Training.” Eur J Appl Physiol. 2015 Mar;115(3): 639-47. doi: 10.1007/s00421-014-3055-y
  8. Hamblin MR. “Mechanisms and Applications of the Anti-Inflammatory Effects of Photobiomodulation.” AIMS Biophys. 2017; 4(3): 337-361. doi: 10.3934/biophy.2017.3.337
  9. Morita T, Tokura H. “Effects of Lights of Different Color Temperature on the Nocturnal Changes in Core Temperature and Melatonin in Humans” J Phys Anthrop. 1996 Sept 15(5): 243-246.
  10. Avci P, Gupta A, Sadasivam M, VecchioD, Pam Z, et al. “Low-Level Laser (Light) Therapy (LLLT) in Skin: Stimulating, Healing, Restoring.” Semin Cutan Med Surg. 2013 Mar; 32(1): 41–52.
  11. Wunsch A, Matuschka K. “A Controlled Trial to Determine the Efficacy of Red and Near-Infrared Light Treatment in Patient Satisfaction, Reduction of Fine Lines, Wrinkles, Skin Roughness, and Intradermal Collagen Density Increase.” Photomedicine and Laser Surgery. Feb 2014; 32(2): 93-100. doi: 10.1089/pho.2013.3616