Dirt is Good For Kids

Chicago TribuneMarch 24th, 2010

By Robert Channick, Special to the Tribune

Presented by:Daniel Ma

Chakrya San

Dirt is Good For Kids…Playing in, and even eating, dirt helps develop immune

system, report says1700 children in Philippines followed from birth to 21 years oldMeasured C-reactive protein (CRP), a predictive biomarker of

cardiovascular heart disease and stroke. CRP level rises during acute inflammation.

kids who had more diarrhea and higher levels of exposure to animal feces as an infant — those individuals had lower levels of CRP

a healthy dose of germs and pathogens during infancy reduced cardiovascular inflammation in adulthood — a precursor to heart attacks and strokes

The study is independent of socioeconomic status, measures of current body fat and other health behaviors

This is the first study linking Hygiene Hypothesis to heart disease

Hygiene Hypothesis Insufficient stimulation by microbes early in life will

lead to more allergy and inflammation. (Strachan, 1989)

The Germless Theory of Allergic Disease. Nature Review, Immunology, Volume 1, 2001 pg 9

Hygiene HypothesisSome support for Hygiene Hypothesis:

Type I diabetes due to autoimmune defects in non-obese diabetic mice can be prevented by virus infection in mice (Oldstone, 1988)

Exposure to at least one course of antibiotics in the first year of life appears to be a risk factor for the development of childhood asthma (Marra, 2006)

Staphylococcal lipoteichoic acid inhibits skin inflammation by acting on keratinocytes (Lai, 2009).

Hygiene Hypothesis Critiques of the Hygiene Hypothesis

The hygiene hypothesis originated not from observations about infection, but from data suggesting a relationship between atopy, family size and birth order (Bloomfield, et al., 2006)Correlation does not imply causation

Asthma cases among inner city children were no less frequent than children in more affluent and hygienic communities (Platts-Mill, 1998)

Some airborne viruses induce or intensify asthma introducing a confounding variable (Folkerts, et al., 1998)

Proponents of the hypothesis suggests renaming it (e.g., the ‘microbial exposure’ hypothesis, or ‘microbial deprivation’ hypothesis) to minimize focus on hygiene and focus attention on impact of microbes on atopic diseases (Bjorksten, 2004)

Questions?