With daylight hours getting shorter it may be tempting to hit the tanning clinic for a top-up of vitamin D but researchers say they now have more evidence sunbeds are too risky. The National Institute of Water and Atmospheric research (NIWA) is conducting an ongoing study, from 2010, to determine the relationship between vitamin D levels in the blood and past personal exposure to UV radiation from various sources including sunlight and sunbeds. Vitamin D is crucial in skeletal development, immune function and blood cell formation. Deficiency has recently been implicated in a wide range of diseases including cancer and heart disease. Early results of the study showed the average UV Index for the sunbeds commonly used in New Zealand is similar to New Zealand summer sunlight (which falls into the extreme category). However, sunbeds produce less vitamin D than sunlight exposure. “More disturbingly, the intensity of radiation at some wavelengths from these sunbeds was several times higher than ever occurs in sunlight at the earth’s surface,” says Dr Richard McKenzie, Principal Scientist, Atmospheric Radiation, NIWA. “By using these sunbeds, we expose ourselves to unknown risks. Our skins may not be able to cope well with this sort of stress.”