Life, whether plant or animal, does not thrive in space as it does on Earth. This presented a challenge for NASA scientists, who wanted to study plant growth in space as a way to feed astronauts on long-range space missions. NASA knew that using traditional light sources, such as incandescent or halogen, was not an option because they were not adaptable to space flight. The main issues with traditional lighting include high heat output and huge energy demands.
LED lights were proposed as a viable option because they are energy-efficient as well as safe—and coincidentally, it was discovered that red light also benefited astronauts. In this article, we’ll explore NASA red light therapy: its beginnings in horticulture, how NASA approved red light therapy and its current uses in human health.
Why NASA Wanted to Grow Plants in Space
It was during the 1980s that NASA scientists began exploring space horticulture. One reason was the human mission to the deep space and other planets that will reshape the future of space exploration—including the colonization of other planets—would require that plants be able to survive extraterrestrial voyages, as well as grow and thrive in microgravity and under artificial light.
Another reason for NASA’s interest in growing plants in space was astronaut health, which was a prime concern during extended space missions. An important part of keeping astronauts healthy is having adequate supplies of nutritious food on long-term space voyages where resupply is limited or nonexistent.
While freeze-dried “space food” was the norm during the heyday of space exploration in the 1960s and 1970s, nothing packs as much nutritional value as fresh, raw vegetables. Because they grow from seeds, vegetables have the added benefit of virtually limitless supply, whereas prepared food must be stored, and freeze-dried food must be reconstituted with water.
But it’s one thing to acknowledge that astronauts need fresh vegetables during space missions … and quite another to actually grow those vegetables in space.
Faced with this formidable challenge, NASA scientists needed to find a light source that did not consume a lot of energy, didn't generate heat and provided the kind of light that was necessary for healthy plant growth. The solution? Light-emitting diode bulbs, more commonly known as LEDs.
LEDs: The Ideal Solution
Ronald W. Ignatius, founder, and chairman of Quantum Devices Inc. (QDI), was the first person to propose using an LED bulb for growing plants. The idea occurred to him during the late 1980s when plant growth experiments were being conducted at the NASA-sponsored Wisconsin Center for Space Automation and Robotics. LEDs, a NASA article explains, “provide high-energy efficiency and virtually no heat, despite releasing waves of light 10 times brighter than the Sun.”
The focus of the research was studying light sources for growing food; specifically, growing food indoors for environments like space shuttles and the International Space Station (ISS), where humans would be present for a long period of time. The NASA research team partnerzed with QDI to determine whether LEDs could provide the necessary light wavelengths and light intensity for photosynthesis to occur.
And as the team hoped, LEDs boosted energy production in plant cells, which promoted growth and photosynthesis.
These first experiments showed great promise, even though the wheat grown aboard spacecraft was leggy and blanched. That finding prompted Ignatius to develop LED products that emit the exact wavelengths of light that plants need for photosynthesis.
NASA then created Astroculture3, a plant growth chamber that uses LEDs to grow plants aboard spacecraft. In October 1995, LEDs made their flight debut on the Space Shuttle Columbia, in the second U.S. Microgravity Laboratory Spacelab mission.
Space Research Continues
Like all technologies, LEDs have evolved throughout the years. Today’s LED lights are more powerful, release less heat, and can be fine-tuned to precise wavelengths that are perfectly optimized for plant and human health.
Since 2012, NASA’s Advanced Exploration Systems (AES) Habitation Projects at Kennedy Space Center’s Space Life Sciences Laboratory have been studying the growth of red leaf lettuce and radish plants under different artificial light sources including broad-spectrum fluorescent lighting, as well as blue and red LED lighting.
The lead researcher on the project was Dr. Matthew Mickens, a plant biologist with North Carolina Agricultural and Technical State University and recipient of the NASA-sponsored Harriett G. Jenkins Predoctoral Fellowship.
As a NASA's Light Therapy Study explains, Mickens studied the plants’ overall growth, including size and density, chlorophyll content, and the presence of adenosine triphosphate (ATP), which is the energy stored in plant cells. Mickens found that radishes exposed to red and blue LED lights grew a darker red, which indicated higher levels of antioxidants.
Eating foods rich in antioxidants, such as blueberries, tomatoes, and red lettuce is important to human health. Boosting antioxidant properties in other plants not known for their antioxidant properties (but high in micro- and macro-nutrients) using red light could have tremendous benefits to astronauts on long-range space missions beyond low Earth orbit.
LED technology is helping researchers optimize plant growth in space. This will eventually lead to the creation of an efficient closed-loop system, in which plants aboard long-range spacecraft would produce oxygen for the crew and even filter/recycle water.
A Groundbreaking Discovery
During NASA’s initial research with LED lights, scientists made an accidental discovery that had profound implications for human health. Not only did the red LED wavelengths boost plant growth; lesions on the scientists’ skin began to heal faster because of exposure to the light.
This was a welcome finding because the microgravity environment on spacecraft is very hard on astronauts’ health. In an article about the discovery, orthopedic surgeon Howard B. Cotler writes: “There is a threefold higher injury rate during mission periods than outside of mission periods for astronauts, and it has been observed that wounds heal more slowly in orbit.”
Another risk for astronauts during space missions is radiation. In space, they aren’t protected by the atmosphere like people on Earth, so they are exposed to high levels of radiation. Spacecraft offer some protection, but according to NASA, astronauts still experience 10 times the radiation they receive on Earth.
Exposure to radiation can cause temporary radiation sickness, as well as long-term risks. Radiation damages the lymphocytes (cells involved in the immune response); causes cancer, circulatory disorders, and cataracts; and may contribute to early-onset Alzheimer’s disease.
Because of all the risks to astronauts’ health, the discovery of red light’s healing properties was extraordinarily exciting. It sparked NASA’s motivation to aggressively pursue more red light studies over the following years, and this research revealed innumerable uses for red light therapy.
How Red Light Therapy Works
One of the primary effects of red light therapy is that wavelengths of light are absorbed into mitochondria, which are “energy factories” inside cells. This stimulates mitochondria to produce more ATP, thereby increasing the cells’ ability to perform essential functions.
Dr. Michael Hamblin, an associate professor of dermatology at Harvard Medical School and a world-renowned expert in red light therapy said,
“Low-level light therapy (LLLT) can stimulate healing, prevent tissue death, and relieve pain and inflammation. The molecular and cellular mechanisms that underlie this effect are under investigation…Stem cells are particularly susceptible to the effects of light and can be induced to differentiate and proliferate.”
Dr. Hamblin’s findings have been confirmed by other studies; since the 1980s, researchers have discovered some key properties that red light has on human health, including increased cellular metabolism, reduced inflammation, increased circulation, reduced oxidative stress, and accelerated recovery from injury.
Wound healing is one application that NASA began studying since wounds heal slowly in microgravity. This research has had far-reaching implications on general human health.
In-flight musculoskeletal injuries do happen, even in microgravity. In 2009, researchers from NASA’s Johnson Space Center cataloged the incidence of musculoskeletal injuries in space. They identified 219 in-flight injuries, with most injuries centering on the hands (abrasions and lacerations) that occurred during transition between modules, exercise, and injuries related to spacewalks using extravehicular activity (EVA) suits. It’s imperative that these sorts of injuries heal quickly, as infection or loss of mobility on a mission could have devastating consequences.
A December 2001 research review focused on near-infrared light therapy in healing ischemic and diabetic wounds in rats as well as acute and chronic wounds in humans. Following are the findings of various in vitro, animal, and human studies cited in the published review:
- In vitro studies found that LED light therapy showed a 140 to 200 percent increase in mouse- and rat-derived fibroblasts (the precursors of collagen, which is critical to wound healing); as well as a 155 to 171 percent increase in the growth of human epithelial cells. Epithelial cells are present in skin and blood vessels and serve as physical barriers to prevent infection by pathogens.
- Studies using near-infrared light in combination with hyperbaric oxygen chambers, which increase oxygen in the blood, found significant decreases in wound sizes in rats.
- In human studies, red light resulted in equally significant accelerated healing of musculoskeletal injuries in Navy SEALs, accelerated wound healing in Navy submarine crew members, and reduction of pain in children with oral mucositis.
One of the most exciting recent developments in the field of red light therapy is as a cancer treatment called Photodynamic Therapy (PDT). PDT uses photosensitizing drugs along with high-intensity red light to target and kill cancer cells. A 2011 study published by the American Cancer Society found that while PDT is still in the developmental stage, it shows promise and offers several significant advantages over surgery, chemotherapy, and radiation including little or no side effects.
Other red light therapy for healing applications include the treatment of neurodegenerative disorders such as Alzheimer’s and Parkinson’s, lymphedema, neuropathic pain, muscle recovery from intense exercise, and osteoarthritic joint pain.
From Space to Your Living Room…
From NASA’s early research to now, LED technology has seen remarkable progress. Now, red light therapy is an effective and safe treatment for innumerable disorders and conditions—and you can use it in your own home with high light-energy output LED red light therapy devices.
There are dozens of applications for red light therapy, backed by thousands of independent studies. Learn more here about how red light therapy can be instrumental in boosting your health and well-being.
Frequently Asked Question
Q. red light therapy discovered by NASA : Is it true?
Ans: Quantum Devices created a light-emitting diode (LED) for NASA's plant growth tests in 1993. 3 The research showed that red LED wavelengths could help plants grow quicker, but they also helped the scientist's skin sores heal faster.