15 minutes $10
The US FDA and the FTC forbid use of the words "safe" or "safer than" regarding indoor tanning, however a benefit claimed by the tanning industry of indoor rather than outdoor tanning is the amount of control the tanner has. They claim that if a person decides to get a suntan, a tanning bed offers an environment that delivers consistent, predictable exposure. In contrast, the amount of UV that reaches the ground can vary from minute to minute and longer tanning times results in deeper exposure.
A frequently claimed benefit of artificial tanning is the increased production of vitamin D. Skin phenotype, as measured on the Fitzpatrick scale influences the skin’s response to UV radiation. Fitzpatrick Types I and II (fair skin, eyes, and hair) burn easily and can produce maximal vitamin D photosynthesis in less than 10 minutes of midday sun. People with Fitzpatrick Types I and II are at the highest risk of photodamage (whether from the sun or artificial tanning) and are at the lowest risk of vitamin D insufficiency if photosynthesis occurs.
In a research project funded by the United States National Institutes of Health and a grant from the UV Foundation, Tangpricha, V. et al. identified, "the regular use of a tanning bed that emits vitamin D–producing ultraviolet radiation is associated with higher 25(OH)D concentrations and thus may have a benefit for the skeleton. The human body can produce up to 10,000 IUs of vitamin D in 10 minutes, as it can with exposure to natural sunlight. This vitamin has many benefits, and many people with indoor lifestyles may not receive enough. Most tanning beds use bulbs with the same UVB relative to UVA rays as the Sun and produce the same levels of vitamin D.