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UV Radiation Information

Health effect and protective measures against UV radiation

Effect of UV radiation on health


A moderate exposure to the sun helps our body to produce vitamin D which could bring increased absorption and better utilization of calcium and phosphorus required for healthy bones and minimized risk of bone fracture.

However, excessive exposure to UV radiation from the sun may cause painful sunburn, wrinkling and premature ageing of the skin as well as an increase in the risk of skin cancers and cataracts.

In respect of skin cancer, about 80% of all cases may be attributable to excessive exposure to sunlight. Specifically, studies suggested that UVA is responsible for the wrinkling, ageing and immediate tanning effects, as well as potential development of skin cancer. Overexposure to UVB may cause sunburn and is one of the  major causes of skin cancer.

In respect of cataracts, the World Health Organization estimates that up to 20% of cataracts may be due to UV overexposure.  

Therefore, one must not underestimate the potential harm UV overexposure may bring.

1. "Global Solar UV Index: A Practical Guide" , World Health Organization, 2002

Department of Health
For more health information related to UV, please visit the webpage of the Central Health Education Unit of the Department of Health.


Last revision date: <27 Dec 2012>