40 women who have developed breast cancer working night shifts in Denmark are receiving compensation from their government.
Dr Vincent Cogliano of the International Agency for Research on Cancer (IARC) said that it believed that alterations in sleep patterns caused by working nights could lower the body's production of melatonin. "Melatonin has some beneficial effects in preventing some of the steps leading to cancer," he told the BBC. He said that the UN agency's finding was based on a wide range of studies. "The level of evidence is really no different than it might be for an industrial chemical," he said. They describe night shifts as being a 'probable' carcinogen, the same as EMFs.
Professor Andrew Watterson, an occupational health specialist at Stirling University, said we are far behind Scandinavia in recognising the dangers of night work. "I think we can say there is a big public health problem here," he said.
In our article on melatonin, we cite some of the studies which link melatonin levels with reduced cancer risk, including breast cancer. Melatonin is a natural anti-cancer agent in the body, but the body can stop producing it when exposed to light at night. Melatonin is produced at night in conditions of darkness, and light switches off the pineal gland's ability to produce melatonin. Exposure to other types of electromagnetic fields (of which light is one) can also reduce pineal melatonin.
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