Both U V B (from the sun) and U V A (from tanning devices) ultraviolet rays can be harmful to the skin. Long-term exposure to the sun or to artificial sources of ultraviolet light (such as tanning devices) contribute to the risk of skin cancer, damage to the eye's retina (if no goggles are worn), and wrinkling of the skin. In addition, tanning devices, like natural sunlight, can aggravate certain medical conditions or react adversely with some medications. Tanning pills have not been tested by the U.S. Food & Drug Administration for safety, and as long-term health effects are not known, they are not a safe alternative to tanning from the sun or an indoor tanning device. The pills generally contain color additives which give an orange tint to the skin. The pills may leave fatty deposits in the blood, liver, skin; and additionally, the 'tan' is not protection against sunburn.