Millions of Americans use tanning beds or sunlamps to maintain a year-round glow—or to get more vitamin D, which is produced when the skin is exposed to ultraviolet (UV) radiation, as from sunlight. Could tanning this way actually be healthy?
Most sunlamps emit primarily UVA, the long-wavelength ultraviolet rays that penetrate deep into the skin and promote tanning. But vitamin D production is triggered by short-wavelength UVB. Some sunlamps produce higher amounts of UVB.