It's an interesting conundrum: The effects of ultraviolet (UV) radiation from sun exposure can induce the onset of, or exacerbate, the symptoms of certain autoimmune diseases. Now flip the coin: UV also can prevent, or reduce, the symptoms of others. Current research focuses on lupus, multiple sclerosis (MS), type 1 diabetes, rheumatoid arthritis, inflammatory bowel disease, dermatomyositis, and atopic eczema.
What is going on? "These irradiations may alter the delicate regulatory network of the immune system to result in an immune dysregulation [overreaction or underreaction to certain substances], and because different diseases are modulated by different types of cells, these effects could be different in different diseases," says Frederick W. Miller, chief of the Environmental Autoimmunity Group at the National Institute of Environmental Health Sciences.
UV radiation encompasses the electromagnetic spectrum from 200 to 400 nanometers in wavelength and is sub-divided into UV-A (320-400 nm), UV-B (290-320 nm), and UV-C. ...
