Asked by: Nic Alford, Ilfracombe
No, for two reasons. First, UV lights in nightclubs typically output at a wavelength of 365nm or longer. This is at the visible end of ultraviolet (which is why you can see a faint purple tinge to the light) and it isn’t energetic enough to trigger vitamin D synthesis. You need UVB light with wavelengths shorter than 315nm for that. Second, indoor lights are only one-thousandth as bright as normal daylight.
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