Water + Fruits + Vegetables = Allergies?

Posted 1.10.13 | Rob McCandlish, RDN

Most Neocate families pose the same question: Why is my child allergic to foods? Or another question common in food allergy circles: Why are more and more people being diagnosed with food allergies? There are many factors that contribute to food allergies, and no single cause can be identified that applies to everyone. But some new research has addressed one of these factors in detail, and it points to several sources, one of which may come as a surprise: tap water.

Microbes, Pesticides, and Allergies

If you’ve taken your child to see an allergist, you may have heard several theories about allergies. The simple version of one theory is that children today spend less time in the dirt, so get less exposure to the environment, and therefore are more likely they are to develop allergies. Or at least that’s the general idea! Past research has also linked pesticides with allergies, but it wasn’t always clear whether it was the presence of pesticides or the absence of bugs (or both) that contributed to allergies.

New Research

Dr. Elina Jerschow is both a professor and a practicing physician in New York. She and several of her colleagues recently published new research into the association between certain chemicals and food allergies. These particular chemicals, termed dichlorophenols, are commonly used in pesticides and weed killers. They may also be present in tap water, either coming from the environment or as byproducts of chlorine compounds. Adding chlorine is one of the most effective ways to ensure that tap water does not contain harmful bacteria.

Dr. Jerschow and her colleagues pulled data on over 2,000 Americans from an ongoing, national collection of health and nutrition data. They specifically looked at levels of dichlorophenols in urine, and compared this to whether or not participants had allergies. The results showed that individuals with the highest urine dichlorophenol levels were almost twice as likely to have at least one food allergy. You can find a summary of the article by CBS here. The research was published in the Annals of Allergy, Asthma and Immunology in December and both a free summary and a link to the full research article, available for purchase, can be found here.


Sometimes we draw incorrect conclusions from research. In this case, we see that people with higher levels of dichlorophenols in their urine are more likely to have food allergies. This doesn’t prove that dichlorophenols cause food allergies, but it does suggest that people with higher exposure to these chemicals are more likely to have food allergies. It could be that dichlorophenols reduce numbers of bacteria in our gut, which may raise the risk of developing food allergies. No association was found between dichlorophenol exposure and environmental allergies.

Avoiding dichlorophenols may not prevent food allergies. However, some people may prefer to try to avoid exposing themselves to high levels of dichlorophenols and pesticides in general. To do so, key steps you can take would be to avoid fruits and vegetables treated with pesticides and to limit consumption of tap water, either straight from the tap or from bottled water that originated from a municipal water supply. If your family drinks tap water, you can let the water sit out, preferably refrigerated in a clean container, for several hours. This gives much of the chlorine in the water time to evaporate, though it may not reduce any dichlorophenols present. You can also use a filter that removes chlorine, but again, we don’t know if household water filters remove dichlorophenols.

Do you think that you or any members of your family may change your food or water habits because of this research?

- Rob


Add Comment

Leave a Comment  Read our Comments & Trackbacks Policy before submitting a comment.

Required fields *

About Us

Food Allergy Living is a resource for parents of children with food allergies, brought to you by Nutricia, the makers of Neocate. For more in-depth information about our purpose & authors, see our About Food Allergy Living page.