Red light has the potential to decrease blood glucose levels, study suggests

A study published in the Journal of Biophotonics indicates that red light has been shown to decrease blood glucose levels by 27.7% after glucose intake, as well as reduce maximum glucose spiking by 7.5%.

Mitochondria, the cellular powerhouse, utilizes oxygen and glucose to generate the energy-rich nucleoside adenosine triphosphate (ATP), vital for cellular processes. Previous research has demonstrated that long-wavelength light ranging from approximately 650 to 900 nanometers, spanning the visible to near-infrared spectrum, can enhance mitochondrial ATP production. This, in turn, decreases blood glucose levels and promotes improved health and longevity in animals. Additionally, researchers discovered that red light at 670 nanometers stimulated energy production within mitochondria, resulting in heightened glucose consumption.

To study the effects of 670 nm red light on blood glucose levels, the researchers enlisted 30 healthy participants. These participants were randomly assigned to two groups: 15 in the 670 nm red light group and 15 in the placebo (no light) group. Excluding individuals with known metabolic conditions and those taking medication, the participants underwent an oral glucose tolerance test. They were then instructed to monitor their blood glucose levels every 15 minutes for the following two hours.

The findings revealed that people who received red light exposure 45 minutes before drinking glucose exhibited a reduced peak blood glucose level and reduced total blood glucose during the two hours.

“It is clear that light affects the way mitochondria function and this impacts our bodies at a cellular and physiological level. Our study has shown that we can use a single, 15-minute exposure to red light to reduce blood sugar levels after eating.” said Dr Michael Powner, Senior Lecturer in Neurobiology in the School of Health & Psychological Sciences at City and also lead author of the study.

“Sunlight has a balance between red and blue, but we now live in a world where blue light is dominant because, although we do not see it, LED lights are dominant in blue and have almost no red in them. This reduces mitochondrial function and ATP production. Hence our internal environments are red-starved. Long-term exposure to blue light is potentially toxic without red. Blue light on its own impacts badly on physiology and can drive disrupted blood sugars that may in the long run contribute to diabetes and undermine health spans.” concludedProfessor Glen Jeffery, Professor of Neuroscience in the UCL Institute of Ophthalmology.”

While the study has only been done in healthy individuals, it has the potential to impact diabetes control going forward, as it could help to reduce potentially damaging glucose spikes in the body after meals

Reference: https://doi.org/10.1002/jbio.202300521