Washington, December 10: Parents who let their kids romp in the mud and get chummy with germs could be helping to protect them against maladies like heart disease later in life, a US study showed on Wednesday.
“Our research suggests that ultra-clean, ultra-hygienic environments early in life may contribute to higher levels of inflammation as an adult, which in turn increases risks for a wide range of diseases,” including of the cardiovascular system, Thomas McDade, lead author of the study, said.
Researchers at Northwestern University in Illinois looked at a study in the Philippines which followed participants from birth to 22 years of age to try to better understand how childhood environments affect production of a protein that increases when there is inflammation.
Inflammation occurs when the body is fighting infection or injury. The data in the Philippines were compiled by tracking the children born in the 1980s to 3 327 Filipino mothers.
Researchers visited the children every two months for the first two years of their lives and then spaced out the visits to every four or five years until the kids reached their 20s.
Developing immune networks
Among items that the researchers assessed were the hygiene of the children’s household environment – “whether domestic animals such as pigs and dogs roamed freely” – and their families’ socioeconomic resources.
Blood tests taken when the study participants reached adulthood showed that although Filipinos suffer far more infectious diseases as infants and toddlers than their American counterparts do, their level of C-reactive protein when they reached adulthood was at least 80% lower than in Americans.
Filipinos in their early 20s had average CRP concentrations of 0.2mg/l, while Americans in the same age group had blood concentrations of the protein of 1-1.5mg/l.
One finding of the study published in the online edition of the Proceedings of the Royal Society was that adults with high CRP levels – not a good thing – were exposed to less animal faeces in the home.
“In the US we have this idea that we need to protect infants and children from microbes and pathogens at all possible costs,” McDade said.
“But we may be depriving developing immune networks of important environmental input needed to guide their function throughout childhood and into adulthood.
“Without this input, our research suggests, inflammation may be more likely to be poorly regulated and result in inflammatory responses that are overblown or more difficult to turn off once things get started,” he said.
—Agencies