Title

Washing Dishes by Hand Can Help Reduce the Risk of Allergies

Watch how researchers are working to make agricultural communities safer for children and families in this four-minute California Matters with Mark Bittman video.

Good news for those without a dishwasher: a new study has found that parents who wash their dishes by hand, rather than in a dishwasher, may unwittingly be reducing their children's risk of developing allergies.

The paper, published in the medical journal Pediatrics, examined an idea called the hygiene hypothesis. The theory suggests excessive cleanliness is the culprit behind America's alarmingly increasing allergies to food, pollen, and other environmental triggers.

Story continues below

Researchers reported that kids who grew up in households where dishes were hand-washed were less likely to suffer from eczema, asthma, or hay fever, as opposed to kids whose dishes were sanitized in a dishwasher.

A possible reason for this? Hand-washing still leaves some bacteria on the dish or utensil. The constant exposure to germs means immune systems are stimulated in early childhood, thereby reducing the risk of allergies developing in later life (by as much as half).

The study, which included 1,029 Swedish children aged 7 to 8, also investigated other behaviors, like whether families followed a "traditional foods" diet of farm-fresh eggs and meat, unpasteurized milk, and fermented foods (which have beneficial bacteria). After controlling for several factors such as day care attendance, parental history of allergies, and whether or not the families had pets, researchers found that only 19% of children from these "traditional" households reported suffering from allergies, versus 46% of children whose dishes were always sterilized in the dishwasher and whose food never came straight from a farm.

The findings suggest that increasing kids' exposure to microbes through the "less efficient" method of hand-washing, as well as feeding them fermented and farm foods teeming with bacteria, can actually be a good thing for their health.

... As if parents needed another reason to get their kids to do the dishes.

Keep Reading