The sun serves many functions. It helps dictate the seasons and brings life to insects, plants, flowers and trees and vitamin D — a vitamin that is produced when the human body is exposed to sunlight — has copious health benefits, from lowering one’s blood pressure to elevating their mood. But a new study published in the journal Microbiome revealed the sun offers yet another perk: It can kill disease-causing bacteria.
The study, conducted by researchers at the University of Oregon, set up 11 identical dollhouse-size rooms. Some of the rooms were exposed to daylight through regular glass, some rooms were exposed to ultraviolet light only and other rooms were kept completely in the dark. The miniature rooms were then filled with dust to replicate an actual living environment and placed outside for 90 days, after which the rooms’ bacterial levels were tested.
The results of the study were not surprising: The rooms exposed to daylight had fewer germs than their darkened counterparts. In fact, the sunlit rooms had 50 percent less viable bacteria. However, researchers did not expect the UV rooms to perform as well as they did.
In fact, the rooms exposed to UV light only fared even better than the naturally lit rooms, as they had the lowest bacteria levels of all.
This study found 12 percent of the bacteria in the dark rooms were viable compared to 6.8 percent in the rooms with daylight and 6.1 percent in the rooms exposed to UV light only.
That said, researchers still do not know what the optimum level of light is — the perfect amount for killing germs, that is — but they hope further studies will yield this information so architects and builders can incorporate this information into future designs.