Is your child’s environment as sterile as an operating room? That might not be a good thing, a leading cancer researcher says in a new report. After three decades of research, Mel Greaves, from the Institute of Cancer Research in London, believes that acute lymphoblastic leukemia (ALL) is caused by a lack of exposure to germs in the first year of birth combined with a genetic mutation that affects one in 20 children, reports the Guardian. Greaves details his theory in the journal Nature Reviews Cancer. The most common type of childhood cancer, ALL affects one in 2,000 children and is increasing by a rate of about 1% annually. Most of the increase is in affluent populations. It is least common in poorest areas, where families are larger and children are exposed to more germs.
Once a death sentence, today 90% of children recover from ALL with chemotherapy, but treatment can have long-lasting health consequences. Greaves recommends that parents make a point of bringing children under the age of one into contact with others. Cancer researcher Charles Swanton believes the research is an important advancement in the medical community’s understanding of how ALL develops but stresses that parents are not to blame for their child’s cancer and that many factors are at work. Sheena Cruickshank of the British Society for Immunology goes a step further and cautions parents not to go overboard on the recommendations. Despite the findings, she says in a statement, "infections themselves can pose a significant risk for young babies with a developing immune system," per CNN. (Read more leukemia stories.)