If you’ve been paying attention the last two decades you’ll have noticed that the mainstream scientific and medical attitudes towards sunlight is altogether negative. Imagine an establishment so inverted that they advise, without a hint of irony, that the creator of all life and sustenance on Earth must be avoided for your own good. This advice was poorly informed even before the discovery that the visible light spectrum yields beneficial biological effects in the skin and in the brain.  Assuming vitamin D were the only product of sun exposure, the deficiency in vitamin D is far more harmful than the risk of potential skin cancers, most of which are non-malignant. The blue wavelengths, at one end, entrain the circadian sleep clock, informing the brain to begin its ~8 hour countdown until sleep. It is balanced with the red and infrared, at the other end, which penetrates the skin by several millimetres to activate heat shock proteins and  energize cells to increase electron flux and produce more ATP. The visible red also reaches back into the midbrain, through the windows that are the eyes, where it protects dopaminergic neurons from damage sustained from excessive blue light stimulation. At the very least, everyone can benefit from plenty of sun outside of UV peak times, when the shadows start to grow long and the light takes on a fiery orange.  The ubiquitous presence of blue light in our homes, absent of the protective red wavelengths, is a modern and unprecedented experiment in human society, and I expect the frequency of age-related degenerative brain diseases to grow in the coming decades while researchers continue to fumble for answers.