Why are allergies increasing?

April 13, 2010

Allergies have become a widespread in developed countries: hay fever, eczema, hives and asthma are all increasingly prevalent. The reason? Excessive cleanliness is to blame according to Dr. Guy Delespesse, a professor at the Université de Montréal Faculty of Medicine.

Allergies can be caused by family history, air pollution, processed foods, stress, tobacco use, etc. Yet our limited exposure to bacteria concerns Dr. Delespesse, who is also director of the Laboratory for Research at the Centre hospitalier de l'Université de Montréal.

"There is an inverse relationship between the level of hygiene and the incidence of allergies and autoimmune diseases," says Dr. Delespesse. "The more sterile the environment a child lives in, the higher the risk he or she will develop allergies or an immune problem in their lifetime."

In 1980, 10 percent of the Western population suffered from allergies. Today, it is 30 percent. In 2010, one out of 10 children is said to be asthmatic and the mortality rate resulting from this affliction increased 28 percent between 1980 and 1994.

"It's not just the prevalence but the gravity of the cases," says Dr. Delespesse. "Regions in which the sanitary conditions have remained stable have also maintained a constant level of allergies and inflammatory diseases."

"Allergies and other autoimmune diseases such as Type 1 diabetes and multiple sclerosis are the result of our turning against us," says Dr. Delespesse.

Why does this happen? "The bacteria in our digestive system are essential to digestion and also serve to educate our immune system. They teach it how to react to strange substances. This remains a key in the development of a child's immune system."

Although hygiene does reduce our exposure to harmful bacteria it also limits our exposure to beneficial microorganisms. As a result, the bacterial flora of our digestive system isn't as rich and diversified as it used to be.

Dr. Delespesse recommends probiotics to enrich our intestinal flora. Probiotics are intestinal bacteria that have a beneficial impact on health. They've been used for decades to make yogurt. Probiotics have a proven effect on treating diarrhea, and studies are increasingly concluding similar benefits for the immune system and allergies.

"Consuming probiotics during pregnancy could help reduce allergies in the child," says Dr. Delespesse. "They are not a miracle remedy, yet they are one of many elements that improve our diet and our health."

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not rated yet Apr 13, 2010
Anyone remember pica and geophagy - in pregnant women and children? Naughty, naughty! Mustn't do that.
5 / 5 (1) Apr 13, 2010
Decades ago, before healthcare was the norm, people took care of their own health, and doctors were expected to only treat broken bones and severe illnesses. These days, many people accept less responsibility in managing their own health, and seem to expect that getting sick is the norm. (This is not addressing those who have honest, chronic illnesses.)

Most of what people experience can be fought by the body if the mind is in the right place. If one believes they are sick or healthy, the body will likely follow suit.

A combination of excessive cleanliness and irresponsibility would exacerbate the issue nicely.
not rated yet Apr 13, 2010
Vit D deficiency is also a factor in asthma.
not rated yet Apr 13, 2010
There's a theory: our immune system is bored. In older times, we frequently fought parasites and other infections non-stop. Our immune system was always active. Without these (like hook worms) our immune system attacks ourselves. Interesting thought.
not rated yet Apr 14, 2010
In that case there should be very little auto-immune disease in populations living in filthy conditions. But, perhaps the stats get skewed because people living in these conditions die of disease (Typhoid, cholera, etc). Also, evolution is pretty good at adapting and tends not to waste energy creating a hyperactive immune system the gets 'bored' sitting around and so starts a fight.

Bacteria and fungi are everywhere. Patients get infected in operating theatres that are designed to be an asceptic environment. No matter how manty times you wash your hands it will be possible to culture bacteria from them. One the immune system detects something foreign it sets about creating antibodies. Perhaps people in 'clean' environments are exposed to the millions of manufactured compounds (cleaning agents, paints, plastics, fibres, etc) and that is the problem. Do the inuit have autoimmune disease ? (Clean environment !). The hypothesis is simplistic and reductionist.
not rated yet Apr 14, 2010
evolution is pretty good at adapting and tends not to waste energy creating a hyperactive immune system the gets 'bored' sitting around and so starts a fight.

Evolution is very good at perfectly balancing out such factors, but evolution is also notoriously slow. If we continue our sterile ways, a hundered generations from now our physiology will require it. However, there will be very little adaptation three generations down the road.
1 / 5 (1) Apr 14, 2010
In my theory even too various food from various geographic locations contributes to allergies because the immune system of people is required to distinguish many foreign proteins and antibodies. In addition, the introduction of GMO contaminated by food bacteria proteins can contribute to allergies significantly. For example, the introduction of GMO soya beans into Great Britain in 1998 has caused a statistically significant step in generally increasing rate of food allergy, because GMO import was enabled in food market stepwise in legal act, i.e. not gradually in this particular case.

not rated yet Apr 15, 2010
Allergies are increasing because they're not killing people any more.

Bee sting a few hundred years ago, you die. Your kids do not grow up to be allergic to bees.

Now a days, bust out the epi-pen have a few kids down the road, buy more epi-pens.
In that case there should be very little auto-immune disease in populations living in filthy conditions.

Actually they did a fantastic study on immigrants in the US. The rate at which people died of autoimmune diseases closely follows how far removed they were from their home country and how advanced their country's medical infrastructure was.

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