(Health Secrets) Spring has a way of luring kids out of the house to play and get dirty. Cleaning them up and doing extra laundry may keep parents busy, but now they can feel better about the grime. Research is showing that kids who get dirty grow up healthier than kids who don’t. Exposure to certain bacteria at young ages helps children develop stronger and more regulated immune systems and lessens the likelihood they will develop allergies.
Fifty percent of Americans aged six to fifty-nine are sensitive to at least one allergen, according to results from a nationally conducted survey by the National Institutes of Health (NIH) from 1988 to 1994, up two to five times from rates found in a similar survey completed in 1980. When the study was released, the researchers were surprised by the increase, but that number has continued to climb steadily since this survey was completed.
The apparent reason for these steadily increasing rates is the more sterile lifestyle we live today. The body’s immune system is formed in reaction to foreign, generally harmless substances such as dirt, animal dander, pollen, mold, and particular foods. The more our lifestyle protects us from encounters with such substances, the greater the chance for a reaction when they are finally encountered.
Exposure to farm animals or pets at an early age could help children avoid developing allergies, according to a study published in the Journal of the American Medical Association (JAMA). This study found that children without pets are more likely to develop allergy related diseases than children with frequent exposure to animals during the first years of their lives.
This study also found that in the past, when families tended to be larger, children had fewer allergies. Today’s children, raised in smaller families, have fewer siblings and are therefore exposed to fewer germs.
Being too clean can impair the skin’s ability to heal, according to scientists at the University of California’s School of Medicine. Normal bacteria that live on the skin of active children, children with pets, and kids who live on farms trigger a pathway that prevents inflammation when they get hurt. This pathway leads to a modulated immune response that reduces redness and swelling, and quickens healing.
Other studies have shown that rats and mice living in sewers and on farms have stronger immune systems than lab rats that live in a clean environment.
The increase in the number of children with food allergies is startling. Thirty years ago, food allergies were extremely rare. Today more than 5 million U.S. children suffer from life-threatening food allergies. The number of children with peanut allergy alone has doubled in five years, and the number continues to grow. Peanut allergies were virtually unknown a few years ago, when peanuts were a popular snack at circuses and carnivals, and the peanut butter and jelly sandwich was the staple of the childhood diet.
For the past several years, theories have been purposed regarding the effects of our sanitized world on our immune systems. However, the development of more and more products for use in the cleaning of our environments has continued. We have been taught by advertisers that the goal of every housekeeper should be a house that is completely germ free and sterile. And we have been taught that parents whose children are dirty from play are negligent. We have bought into the idea that no matter how many toxic ingredients are contained in household and personal care products, they should be used with ever greater frequency in our homes and on our bodies.
Now scientists are showing that we’ve got it wrong. Stamping out innocuous organisms is weakening children’s immune systems, and allowing other parts to develop unchecked. Such imbalance triggers a host of illnesses, including asthma, allergies, and even such autoimmune diseases as rheumatoid arthritis and type1 diabetes.
For several years scientists have uncovered signs that illness can result when the immune system does not get enough practice fighting bacteria and viruses. Several epidemiological and experimental studies have converged to put this hypothesis on firm ground.
These studies haves determined that one arm of the immune system, specialized white blood cells called Th1 lympocytes, conducts a direct assault on foreign invaders in the body. Counterbalancing this, another arm of the immune system involving a different variety of white blood cells, Th2 lymphocytes, tries to block dangerous microbes from invading cells in the first place. Th2 lymphocytes also drive allergic responses to foreign invaders.
The infant’s immune system appears to rely primarily on the Th2 system. The Th1 system, designed as the counterbalance to the actions of Th2, can grow stronger only if it gets exercise, either through fighting infections or through encounters with microbes. Without such stimulation, the Th2 system predominates and the immune system gravitates toward allergic responses.
Julian M. Hopkin and his colleagues at the University of Wales Swansea reported on a study of 867 Japanese children vaccinated against tuberculosis. Those who showed a strong Th1 response, indicating previous exposure to the TB bacterium, had far fewer allergies and asthma than did those who showed no Th1 response.
Although it had been thought that the Th1 system required periodic infections during childhood in order for it to stay sturdy, researchers now argue that the main problem is that children and their environments have become squeaky clean. They suspect that children need contact not with disease-causing microbes, but with bacteria in soil and untreated water, particularly with organisms called mycobacteria, to give their Th1 systems a workout.
The continuing rise in allergies since the NIH study coincides with the acceptance and use of antibacterial soaps and hand sanitizers, the ultimate in excessive cleaning. Antibacterial soaps are applied to hands and bodies in the shower or during hand washing with warm water, meaning that they easily enter the body while pores are open and gain access to the blood stream.
Hand sanitizers are applied to the hands and rubbed in, not rinsed off. As a result, the active ingredients in them, the ones that actually kill bacteria, enter the body where they have immune suppressing effects. There is gathering evidence that these anti-bacterial ingredients are also carcinogenic.
When your children come in from play, have them wash their hands the old fashioned way, with regular soap and water. When hands are washed this way, bacteria are sent down the drain, not killed, and no killer substances enter your child’s bloodstream.
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