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. (Both UVA and UVB damage skin and increase skin cancer risk.) Some sunlamps do, however, produce higher amounts of UVB, more in line with sunlight, and some are designed specifically for vitamin D production.
- Sperti Vitamin D Lamp ($425). This portable sunlamp, which has special fluorescent bulbs that produce UVB, is the only one approved by the Food and Drug Administration (FDA) as a “Vitamin D Lamp.” The lamp's timer allows user to expose themselves to the rays for only five minutes at time. The lamp can increase vitamin D levels in people with nutrient-absorption issues—but even for them, there are preferable ways to get vitamin D, notably very large oral doses or injections.
- Dr. Mercola’s D-Lite System ($1,600 and up). Available as a stand-up or bed model, these sunlamps emit UVB rays (for vitamin D production), along with red light (for “all-round skin rejuvenation”). Other sunlamps in his line of tanning devices provide UVA (for tanning), blue light (which “can actually help your skin health”), and infrared light (for “temporary relief of pain and stiffness”). While there is some evidence that red and blue light, as well as infrared light, might have some skin and other health benefits, such treatments should not be done in conjunction with harmful UVA and UVB. No lamps that emit UV can be considered safe. Save your money.