Modern, germ-free lifestyles could be responsible for most common type of child cancer

The modern, germ-free lifestyles many children lead could be responsible for the most common type of cancer in children - acute lymphoblastic leukaemia - according to one of the UK’s most well-respected scientists.

Professor Mel Greaves, from the Institute of Cancer Research, has been studying for 30 years how the immune system can become cancerous if it is not exposed to enough bugs early in life.

Acute lymphoblastic leukaemia affects one in 2,000 children and is more common in advanced, affluent societies, suggesting cleaner modern lifestyles could play a defining role.

Prof Greaves says the disease happens in three stages: a genetic mutation inside the womb, a lack of exposure to microbes in early life and an immune malfunction and leukaemia in childhood. He believes that it could be possible to prevent the condition.

Prof Greaves said: "The research strongly suggests that acute lymphoblastic leukaemia has a clear biological cause and is triggered by a variety of infections in predisposed children whose immune systems have not been properly primed."

Unfortunately, preventing the disease isn’t as simple as exposing children to dirt. They need, according to Prof Greaves, contact with beneficial bacteria. The best way to do this is to give them a safe cocktail of bacteria, such as in a yoghurt drink, that will help boost their immune system.

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