Gluten Detectors and Test Kits: Nima, EZ Gluten, and GlutenTox Home

Gluten testers are devices designed to tell you whether something you plan to eat contains gluten. Some of the most popular gluten test kit brands include EZ Gluten, Nima, and GlutenTox.

When properly used, a gluten tester may be able to tell you whether a food has gluten in it, but these testing methods have drawbacks. They can be expensive and they may give you false positives (indicating a food has gluten in it when it actually doesn't). They may also give false negatives (indicating a food doesn't have gluten in it when it actually does). Some can be difficult to use, which means they may not be practical for the dinner table.

This article discusses three gluten testing options—Nima, EZ Gluten, and GlutenTox, including their costs, benefits, and drawbacks.

Pros and Cons of Gluten Test Devices

Gluten testers are widely available and there are several brands to choose from. They give you the ability to test for gluten without having to rely on a label or someone else's assessment of a food or product. They take some of the guesswork out of meal choices and may be able to identify gluten when it's otherwise difficult to know it's there.

Unfortunately, there are drawbacks to using these devices. They tend to be expensive and may be out of reach for some people. They aren't always convenient to use, and false negatives and positives are common.

Are They Accurate?

The National Celiac Association does not currently recommend any of the available gluten testers. This is because gluten testers are often inaccurate and may give gluten-sensitive people or people with celiac disease a false sense of security. 

Gluten testers are only accurate in samples containing a certain amount of gluten. Sometimes they also give inaccurate results with foods that contain gluten within the range they are designed to detect. They also don't tell you how much gluten is in a positive sample. 

These inaccuracies may mean you'll eat gluten-containing products that the test kit misidentified as gluten-free. You may also needlessly avoid products that would have been safe for you to eat.

Nima Gluten Tester

The Nima gluten tester is a battery-powered, rechargeable device small enough to fit in a pocket or purse. To use it, you load it with a one-time-use disposable testing capsule, insert a large crumb-sized sample of the food you want to test and wait about three minutes until the testing is complete.

The Nima's display will light up either with a smiley face to indicate the food is gluten-free or with a wheat icon and the text "gluten found."

Benefits

Nima is easy to use and its results are easy to interpret. It's possible to test almost every type of food with Nima, including baked goods, fried items, soups, sauces, and desserts. You also can sync the tester with your iOS device, which allows you to review your own test results and contribute to a crowd-sourced database of test results.

Drawbacks

Nima is expensive to buy and expensive to use. The device retails for about $219 (prices subject to change) and does not come with the capsules you need to perform the test. Bundles of six capsules each are sold separately for $39.99. This means it will cost around $20 to test a main course, side dish, and dessert during a single meal.

Nima only tests food to the legal limit of fewer than 20 parts per million of gluten. If the food contains trace gluten below the legal threshold, Nima will still display a smiley face. If you're one of the many people who react to trace gluten below 20 parts per million, Nima may not work well for you.

The device also won't necessarily detect gluten cross-contamination in foods. For example, if a bread crumb was left on the same chopping board a chef used to prepare your food, Nima won't be able to detect it unless it was in the test sample. This might give you a false sense of security about what you're eating.

EZ Gluten Test Kits

EZ Gluten will detect gluten levels as low as 10 parts per million—half as much as Nima. You also can use this test kit to test for gluten cross-contamination on a surface, although doing so requires the use of sterile test swabs.

Benefits

EZ Gluten's main benefit is that it's sensitive to lower levels of trace gluten. Many people with celiac disease and gluten sensitivity find they react to gluten levels well below the legal standard of 20 parts per million currently allowed in gluten-free products. EZ Gluten can help you pinpoint a reaction or identify products with lower gluten levels than that standard.

Drawbacks

Like Nima, EZ Gluten test strips are expensive. A five-pack costs around $63 on the company's website and a package of 25 test kits retails for $276.

The test kits are not easy to use. The sample needs to be ground to a fine consistency to make the gluten easier to detect. Then, it's mixed thoroughly into a liquid solution and added to a test tube. A test strip is placed into the test tube and it takes 10 minutes to see the results. This makes the EZ Gluten test impractical to use while dining out.

Interpreting the test is also not straightforward. The test has three lines; various combinations of these lines mean different things, ranging from "negative" to "high positive" and "very high positive." There's also a result that means "invalid test." A very faint positive result can require a magnifying glass to detect.

GlutenTox Home Test Kits

GlutenTox manufactures professional-grade gluten tests along with a consumer version of its technology, GlutenTox Home. GlutenTox Home will detect gluten as low as 5 parts per million. That makes the test twice as sensitive as EZ Gluten and four times as sensitive as Nima.

GlutenTox Home is somewhat more complicated to use than EZ Gluten. The food needs to be ground into a powder before it's added to an extraction vial. Then the sample is added to a dilution vial where it is shaken for 15 seconds. A few drops of the solution are then added to the vial's cap, and the test strip is dipped into the cap. It takes 10 minutes to get results but the whole process takes around 20 minutes to complete.

The GlutenTox test strips themselves are easier to interpret than the EZ Gluten test strips. There are two lines: a blue control line that shows you the test is working properly and a pink positive result line, which only appears if there's gluten in the sample. The pink line will appear darker for high concentrations of gluten and lighter for low concentrations. A positive result may be too faint to see without magnification.

Benefits

The main benefit of GlutenTox Home is that it is far more sensitive than EZ Gluten and Nima. This makes it a good choice for people who are highly sensitive to gluten.

Drawbacks

GlutenTox Home is significantly more difficult to use than Nima and a little more difficult to use than EZ Gluten.

Like Nima and EZ Gluten, the GlutenTox Home test kits are expensive: They range in price from $36 for two kits to $144 for ten kits.

Summary

Gluten testing devices can help you identify gluten in the foods you eat. The three most popular choices have varying levels of sensitivity: Nima, EZ Gluten, and GlutenTox Home. Nima is easy to use but not as sensitive as the other two options. EZ Gluten and GlutenTox Home are more difficult to use but more sensitive.