A little dirt doesn’t hurt

Mahatma Ganhi, the leader of India’s independence movement, popularized the expression, “Cleanliness is next to godliness.” Any doctor would agree that cleanliness is on the pathway to health nirvana. But are we going too far in keeping young children isolated from common germs? Are some parents doing a disservice to their youngsters by keeping them too clean?

For decades, immunologist have been studying whether exposing young children to a little dirt might strengthen the ability of their immune systems to fight infection later in life.

Research by Sir Mel Greaves, professor of cell biology at the Institute of Cancer Research in London, England, shows that children raised in cleaner environments are more likely to have weakened immune systems.

But experts are concerned an absence of exposure to common infections early in life may even be responsible for some children developing Acute Lymphoblastic Leukemia (A.L.L.).

A.L.L. is the most common cancer in children 4 years-andunder and its global rates are increasing. This malignancy affects white blood cells in the blood stream and bone marrow and can quickly spread to other organs. The treatment is chemotherapy, radiation or the use of stem cells. But Greaves, who was knighted for his research, says some cases may be preventable.

Greaves says some children may be genetically predisposed to A.L.L. But, he adds, only one per cent of these children develop this disease and that the disease is more prominent in affluent societies. So, Greaves suggests an environmental reason may be the cause.

Greaves believes acute lymphoblastic leukemia is linked to childhood infection. He says that, for most children, their immune systems are able to handle infectious attacks. But for those children with a weakened immune system these infections can trigger leukemia.

This suggests that it is important in the first years of life for the immune system to be primed for infections it can handle. Children need to build their defense system while they are young against common germs that won’t harm them. If they don’t, their immune systems may be overwhelmed later on by attacks that cause more severe consequences.

Many readers may share my skepticism that dirt can be good for us. Afterall, I have Gandhi and godliness on my side. But perhaps we should think of childhood as the proving grounds to prepare for battles to come later in life. It’s logical that our immune system requires time to develop an effective defense. Modern medicine seems to have forgotten the power of natural immunity. And we now know that nearly 80 per cent of the immune system is in our gut and we require healthy bacteria

to support immunity.

Greaves says that there are many causes for a weakened immune system. Today, we receive heavy toxic loads from agriculture, chemicals, radiation, and pollution, which can all create inflammation.

We also know some parents are excessively protective, safeguarding their children from every source of germs. Their children are in what Greaves calls a Lysol Prison . . . . .

Greaves believes that chronic inflammation is the root cause of many diseases. It’s not a new idea, as researchers have linked heart attack to underlying inflammation.

His research is now exploring ways to prevent childhood cancer. He is analyzing bacteria, viruses and other organisms in the gut to help prime the immune system. The hope is to produce a cocktail of microbes that can be given to children as a yogurt-like drink.

I hope it's successful. One of the most depressing sights I’ve ever witnessed occurred at the Great Ormond Street Hospital, in London, England, where I saw young children dying of cancer. Greaves also attributes his decision to study leukemia to his own visit there.

So, keep children clean, but don’t be obsessive. The best defense against infection is a strong immune system.

Dr. W. Gifford-Jones is a syndicated columnist whose medical column appears in The Guardian every Tuesday. Check out his website, www.docgiff.com, which provides easy access to past columns and medical tips. For comments, readers are invited to email him at info@docgiff. com. He can also be found on Twitter @ GiffordJonesMD.