Vitamin D

• Vitamin D aids in the absorption of calcium in the digestive tract and keeps calcium levels consistent in our bodies. The vitamin does not occur in many foods naturally. However, production of the vitamin can be triggered by exposure to ultraviolet rays.
  
  

Ultraviolet Rays

• The sun emits light in two forms of ultraviolet rays: UVA rays and UVB rays. UVA rays penetrate deep into the skin, whereas UVB rays affect the outermost layers. The UVB rays trigger vitamin D synthesis.
  
  

Tanning Beds

• Tanning beds aim to tan the skin of the user without burning. Because of this, tanning beds emit mainly UVA rays. While this may create dark tans, these rays do not produce vitamin D.
  
  

Exposure

• Exposing the bare skin to UVB rays will trigger Vitamin D production. In the sunlight, the recommended exposure time for the face and arms is about 20 minutes per day. In a tanning bed, this time would be much less because the whole body is exposed and the UV rays are concentrated.
  
  

Considerations

• Increasing Vitamin D levels through tanning bed exposure is not as good as exposure to natural sunlight. However, with regular tanning bed use you will be exposed to low levels of UVB rays, which can still trigger vitamin D synthesis.