Allergies and Asthma: Dogs, Bacteria and Dust, Oh My!

probiotics, dogs and allergies

Probiotics and pets help fight off allergies

The first 2 years of your child’s immune system are the most critical. Breast feeding, pets in the home, antibiotics, vaccinations–all these play a roll in the rest of your little one’s life.

Let me amend that–the prior 9 months before the two years start are equally as important.

Either way, the immune system does not come fully programmed; rather, it needs to be tamed by teaching it to attack what it is supposed to attack and recognize as friends our own tissues. The gut plays a large role in this process since 2/3 of immune cells interact with the gut at some point in their life cycles.

This is why having the right bacteria is so critical as is avoiding antibiotics unless absolutely critical. Antibiotics decimate the bacteria in our guts that can take years to re-balance.

As an animal lover, currently housing a near-zoo consisting of a salt water tank, three small fish tanks, 5 dogs, 3 lizards and a bearded dragon (which is actually a lizard as well but seems unique enough to warrant it’s own category), I think that having pets for children is a good idea anyway and teaches many lessons in life. Beyond that, there has been research supporting the fact that when children are exposed to animals at a very young age (that “under 2” thing again) the risks of developing asthma and allergies is lower.

This falls under the “hygiene hypothesis,” where our increasingly sterile lifestyles are not training our immune system for challenges. This lack of training leads to the development of immune system disorders. With this in mind, I think the way this particular article brings all of this together is just short of awesome.

Keeping in mind that this was a mouse study, there is no reason to doubt that the same pathway works in us. Here’s how it goes:

  1. Dogs carry dust into the household.
  2. This dust then has an effect on the bacteria in the gut, increasing levels Lactobacillus johnsonii, which has been shown to tone down allergic inflammation in the airways.
  3. This results in reduced Th2 cytokine production, fewer activated T cells.

Wow. Talk about a convoluted web! Either way, this study really strongly reinforces the hygiene hypothesis, showing that it requires dirt, dogs AND bacteria for the full beneficial effect.


James Bogash

For more than a decade, Dr. Bogash has stayed current with the medical literature as it relates to physiology, disease prevention and disease management. He uses his knowledge to educate patients, the community and cyberspace on the best way to avoid and / or manage chronic diseases using lifestyle and targeted supplementation.