Consumer Testing for Gluten

There are currently several testing kits which may be used by the consumer  to detect gluten in food.  These kits include Ridascreen Quick Gliaden, EZ Gluten, AgraStrip Gluten G12 and Gluten Tox testing kits. There is also a device called NIMA. The technology used by these kits to test for gluten is different from that used in industry.  The gold standard for testing is the R5-ELISA test. The home testing kits use a lateral flow method of testing which is not as accurate.  The home test kits screen for the whole proteins that provoke symptoms of Celiac but can miss them in foods which have been processed or are a mixture of ingredients. The mixture makes it more difficult to detect the proteins. Some processing breaks up the protein also making it difficult to detect by these kits. The kits were validated on pure foods e.g. wheat flour. They were not validated to detect gluten which is mixed with other ingredients. The NIMA testing device is also expensive. The device costs $200. and a kit of 12 single use tests sells for $60. The NIMA also further muddies the water by reporting foods as "low gluten" or "high gluten".  Tricia Thompson, M.S.,R.D. of has used the NIMA to test various food samples. The  test results were cross checked for accuracy by also sending the samples to a lab for R5-ELISA testing. By FDA rules, a food may be labeled "gluten-free" if it has 20ppm or less gluten. The NIMA labeled a sample with 1ppm as "low gluten". This might indicate to the consumer to avoid this product when it falls within guidelines for gluten-free. Furthermore, tests done in a lab are protected from the cross-contamination and mishandling that could occur when done outside of these controlled conditions.  So, the jury is still out on just how useful these tests are to the consumer.

New on the horizon are two tests to detect gluten after it has been consumed. These are awaiting FDA approval which may come by the end of this year. One test detects gluten in urine and the other tests for it in a stool sample.  The urine test can be performed at home by the consumer.  The stool test needs to be sent to a lab for analysis. The urine test would confirm that someone has been exposed to gluten within the last 24 hours. It would be helpful to learn if there had been inadvertant gluten exposure.The test would help answer questions as to whether a person's symptoms were due to gluten exposure or some other cause.  These tests would also help researchers testing the effectiveness of anti-gluten medications. At present, the researchers need to rely on the  recall by study participants to know whether or not they have ingested gluten. The stool test will be marketed to physicians. It will detect gluten exposure over a period of several days prior to testing.  This test will help health professionals determine how closely an individual is following the gluten-free diet. The test will also help patients discover if they have inadvertantly consumed gluten. Both tests are quicker than the blood tests currently in use. Watch for Gluten Detect kit in pharmacies by the end of the year.