In addition to triggering vitamin D production, the sun may have other health benefits. University of Edinburgh researchers studied 24 healthy volunteers that used lamps that produce ultraviolet A (UVA) light mimicking the sun’s UVA rays, compared with similar lamps that only produce heat. Two sessions under the UVA lamps significantly lowered blood pressure and boosted nitric oxide levels in the blood. The latter is linked to better circulation. The scientists concluded that the combined effect may help prevent heart disease.