Shining red light on back could help lower blood sugar levels

A senior woman recording her blood sugar level with a smartphone. (Photo: Getty Images)

London, February 23, 2024: A new study has suggested that shining a red light on someone’s back could help lower their blood sugar levels.

The research found that using a specific frequency of light for 15 minutes led to a 27.7 per cent drop in blood sugar levels after eating something sweet, and it also reduced the highest spike in glucose by 7.5 per cent. Spikes are when your blood sugar level quickly goes up after eating certain foods.

The scientists believe their findings could have big effects on our health in the long run, including the chance that blood sugar could be negatively affected by being exposed to blue light for a long time. With LED lights being so common these days, and because they give off more blue light than red, the researchers think this could be a potential “health span time bomb”.

They suggest that blue light alone could cause disrupted blood sugars that might eventually lead to diabetes and shorten a healthy lifespan. But they say spending more time in sunlight could help. Even though the study was done on healthy people, the technique could potentially affect how diabetes is controlled after meals, as it can reduce harmful changes in blood glucose that contribute to ageing.

Dr Michael Powner, who led the study and is a senior lecturer in neurobiology at City, University of London, explained: “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.”

“While this has only been done in healthy individuals in this paper, 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.” Professor Glen Jeffery, a Professor of Neuroscience in the UCL Institute of Ophthalmology, said: “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.”

“Pre-1990, we all had incandescent lighting which was okay because it had the balance of blue and red similar to sunlight, but there is a potential health span time bomb in the change to LEDs in an ageing population. This can partly be corrected by spending more time in sunlight.”

The study found that at a frequency of 670 nanometers (nm) red light stimulated energy production within mitochondria, the tiny powerhouses within cells, leading to increased consumption of glucose. In previous studies, 670 nm light shone selectively onto the backs of mice showed improvement of a molecule, called adenosine triphosphate (ATP), that improves symptoms in both a model of Parkinson’s disease, and a model of diabetic retinopathy – loss of vision in people with diabetes.

Previous research established that long wavelength light between approximately 650-900 nm can increase production of ATP which reduces blood glucose and also improves health/lifespan in animals. In the study, researchers recruited 30 healthy people, who were put into two groups – 15 in the 670 nm red light group, and 15 in the no light group. They were then asked to drink glucose dissolved in water and record their blood glucose levels every 15 minutes over the next two hours.

People who received red light exposure 45 minutes before having the drink exhibited a reduced peak blood glucose level and reduced total blood glucose during the two hours. The study, published in the Journal of Biophotonics, was sponsored by Sight Research UK.

Keith Frayn, emeritus professor of human metabolism, and emeritus fellow at Green Templeton College, University of Oxford, said: “If confirmed later in people with diabetes, this could be the foundation of a useful intervention. But these intriguing findings should be regarded as quite preliminary. More investigations would be needed before we can fully assess this effect.”

“Importantly, we need to know whether this is a true metabolic effect, or whether, for instance, the warming effect of the red light exposure alters patterns of blood flow, potentially altering the nature of the blood sampled by pricking a finger. We also need more information on what happens to the glucose that doesn’t appear in the blood.”

Courtesy: Mirror