Hand-Washing Dishes Is Good For Your Immune System

Iron Chef Masaharu Morimoto, a superstar on "Iron Chef America," once said: "Japanese chefs believe our soul goes into our knives once we start using them. You wouldn't put your soul in a dishwasher!"

He's right; that modern utility isn't very soulful, but for a newly discovered and surprising reason. A Swedish study found that kids who grow up in households using dishwashers are more likely to develop allergies, eczema and asthma than kids in households where dishes are hand-washed. (In the same vein, another study found that if parents clean off their kid's pacifier by sucking on it, the children develop fewer allergies.)

The researchers followed over 1,000 7- and 8-year-olds. They found that 38 percent of kids whose parents had dishwashers reported eczema, while only 23 percent of hand-washers did. And in dishwasher families, 7.3 percent of the kids developed asthma, while only 1.7 percent of kids in hand-washing families did.

Why? Well, it could be another vote for the hygiene hypothesis. That theory says our lack of exposure to microbes makes us susceptible to autoimmune disease, allergies, etc. Perhaps a dishwasher's wash-and-dry cycles don't leave any immune-system-strengthening germs on dishes for us to ingest.

But we're not saying you should give up your dishwasher (it may be soulless, but it sure is convenient); just don't get oversanitized. Lose the antibacterial soaps and household cleaners; they trigger antibiotic resistance, and their chemicals often include hormone disruptors! Trust your immune system. Soap, water and elbow grease to do a fine job.

© 2015 Michael Roizen, M.D. and Mehmet Oz, M.D.
Distributed by King Features Syndicate, Inc.