Every action, they say, has an equal and opposite reaction. Could that be happening to our obsession of keeping ourselves away from bacteria, parasites and worms? Scientists are beginning to investigate why autoimmune diseases are on such a steep rise ever since our bodies have become accustomed to germ-free potable water, sterile food and sanitized homes and offices. Now known popularly in scientific circles as the hygiene hypothesis, Dr David Strachan, was the first to draw the world’s attention to the unpleasant consequences of excess sanitation, through a scientific article published in the British Medical Journal in 1989.

He observed that ever since we have moved to sanitized living and distanced ourselves from “healthy” or “friendly” germs, parasites and worms (most of which were indeed friendly but were mistaken to be harmful because of a bad few they were associated with), our immune system has not had enough stimulus to mature in our infancy and childhood. Scientists are now exploring a connection between the surge in immune disorders of recent times such as asthma, eczema, Type 1 diabetes, multiple sclerosis, ulcerative colitis and inflammatory bowel diseases by this phenomenon.

When the body’s immune system gets its first exposure to germs somewhat late in life perhaps, it is often responds in an intolerant violent manner rather than with tolerance that comes with early exposure. Hence it directs its wrath against host organs to create diseases loosely referred as “auto- immune”.

Getting rid of cholera, typhoid, tuberculosis, small-pox, polio and such diseases through sanitation and vaccination have undoubtedly helped give us longer lives. But science seems to be coming a full circle and telling us that “artificial” living may not be all that healthy after all.

Every time children of my friends from USA come visiting India, they invariably come down with abdominal cramps and loose stools despite all the bottled water we can provide. We native Indians do not seem to react that way!

Strachan’s original hypothesis had also centered on family size and staying close to nature. He had observed that people living together in large families had less incidence of autoimmune and chronic inflammatory disorders as those staying in suburbs or ranches, perhaps with pets and animals.

A recent message circulating on social media congratulated those who have survived the 1950s, 60s, 70s. Yes, most drank water from the taps, ate street food at venders who served with ungloved hands, did not use hand sanitizers five times a day, and yet did not seem to have suffered as much from allergies and autoimmune diseases as those born later in “affluent” homes.

And healthy germs do not have to come in small bottles or capsules to be consumed as medicines! It is time we came out of sanitized homes and rubbed shoulders with friendly germs.

Dr Gourdas Choudhuri is the Director & Head of Department of Gastroenterology and Hepato-biliary Sciences at Fortis Memorial Research Institute.