Neuroscientist raises concerns about potential health effects of LED lighting

LED lighting has become standard in homes, offices, schools and hospitals because of its energy efficiency. However, University College London neuroscientist Glen Jeffery has raised concerns that prolonged exposure to LED-dominated lighting could affect mitochondria and potentially have broader effects on health.

Jeffery argues that the relatively high proportion of short-wavelength blue light emitted by many LEDs, combined with their limited infrared output, could influence mitochondrial function. Mitochondria are responsible for producing energy inside cells and play an important role in metabolism.

Some research supports the possibility that different wavelengths of light can affect biological processes. Studies in mice, for example, have reported changes in mitochondrial activity and metabolic processes following exposure to blue-enriched LED light. However, such findings do not establish that normal exposure to LED lighting causes metabolic disorders in humans. (⁠Newsmax)

Jeffery and colleagues have also studied the effect of different types of indoor lighting on vision. In a study involving 22 adults, participants exposed to broader-spectrum tungsten lighting for two weeks showed improvements in colour-contrast vision, while those exposed to standard LED lighting did not. The researchers have suggested that the lack of longer wavelengths, including infrared light, may be relevant. 

Jeffery has compared the potential health implications of LED lighting with those of asbestos and described the issue as a public health emergency. These characterisations, however, go beyond what current evidence has established.

The European Commission’s Scientific Committee on Health, Environmental and Emerging Risks has concluded that there is no evidence of direct adverse health effects from LEDs when they are used normally by the general healthy population. The committee does acknowledge that light can affect circadian rhythms and that more research is needed to determine the long-term consequences of such effects. (⁠Public Health)

The committee also notes that the intensity, spectrum and duration of exposure are important when assessing potential risks. Exposure to artificial LED lighting is generally much lower than exposure to natural light outdoors. 

For now, there is no established evidence that ordinary LED lighting causes diabetes or other metabolic diseases in humans. The research does raise questions about how different forms of artificial light may affect biological processes, but further studies are needed before stronger conclusions can be drawn.