Exposure to short wavelength light absorbed by mitochondria is associated with weight gain, shifts in cytokine expression and anxiety-like behaviours.

Mitochondria absorb short wavelengths around 420nm. This is associated with reduced ATP and restricted mobility. The 420-450nm range is a significant element of LED lighting and computer monitors. Here we expose freely moving mice to 420nm or 450nm lighting and show rapidly weight gain within a week. This may be due to reduced mitochondrial demand for circulating carbohydrates. Both groups displayed marked shifts in serum cytokines. Open field mobility was examined. The distance travelled was similar between both experimental groups and their controls. However, both experimental groups showed avoidance of central regions consistent with anxiety-like behaviours. This was significant in the 420nm group whose wavelength exposure is closer to peak mitochondrial absorbance. These data demonstrate the potential hazards of exposure to specific short wavelengths in the visual range now common in the built environment. Data are consistent with a wider literature on systemic problems arising from exposure to short wavelength light.