As many of you know, some individuals are allergic to the metal nickel.
This usually manifests as redness of the skin, which occurs when the skin comes in contact with nickel. This is what we might call a more classic allergic reaction, different from the hidden types of food allergies that are more commonly discussed.
A nickel allergy is often discovered when exposure to an item of clothing or jewelry leads to a read rash. This may occur when a fastener made from nickel, such as the button on your pants, comes into contact with your belly and leads to a rash. Or when a piece of jewelry containing nickel, such as an earring, bracelet, watchband, etc. comes into contact with your skin and causes a rash. These reactions are often readily apparent to the wearer and are called contact dermatitis. But nickel allergies can also trigger eczema on other areas of the skin.
What does all of this have to do with digestive problems?
Far more than you might imagine. The digestive tract is a highly specialized extension of your skin. It is a continuation of the epithelial tissue that surrounds the rest of your body. Therefore, it should not be too surprising to realize that if something affects your skin, then it could also impact your digestive tract as well and cause abdominal pain, diarrhea, and other digestive problems. An astute reader recently wrote us and asked why we had never talked about this before. Frankly, it never occurred to us. But upon further investigation, it certainly makes sense.
How Your GI Tract Gets Exposed to Nickel
Some foods are particularly high in nickel. When you ingest them the lining of your digestive tract is exposed to nickel. And like your skin, it is possible that the nickel can trigger an inflammatory reaction, except within your digestive tract.
Not everyone who has a skin reaction to nickel will necessarily have a digestive problem from ingested nickel. Only people especially sensitive to nickel will notice this reaction, because the nickel is a not maintaining constant contact with the epithelial tissue at a high dose like is in the case of earrings or buttons on pants. But if you do have a skin reaction to nickel, it is certainly something important to consider.
Foods That Contain Nickel
Foods known to be high in nickel include chocolate (cocao), coffee, tea, nuts, soy beans and other legumes, and even oatmeal. Canned food is also often higher in nickel. But remember, just because you react to one or more of these foods does not necessarily mean that it is because of a nickel allergy. There are many other reasons that people can react to the foods listed above.
You may already know if you have a serious reaction to nickel due to a skin reaction, but in some cases your digestive reaction may not be that obvious. Conventional allergists offer a patch test that can help, but is far from perfect. And in some cases the only way to sort is out is to do a trial diet low in nickel.
Unfortunately this is the only treatment as well, but it is possible to do. And if it isn’t solving your problem, then please come and see us. We’ll try to help you sort out the rest.
(photo: creative commons)
Picarrelli, A, et. Al., Oral Mucosa Patch Test: A New Tool to Recognize and Study the Adverse Effects of Dietary Nickel Exposure.
Biol Trace Elem Res. 2010 Mar 5. [Epub ahead of print]
Sharma AD. Relationship Between Nickel Allergy And Diet. Indian J Dermatol Venereol Leprol 2007;73:307-12
Dr. Stephen Wangen is the award winning author of two books on solving digestive disorders, and a nationally recognized speaker on IBS. He has been on ABC, NBC, and Fox as well as public radio. He was recently named one of Seattle’s Top Doctors by Seattle Magazine.