Controversial Aspects of the Gluten-Free Diet: All About Wheat Starch

Historical Nugget

In some parts of the world, wheat starch has always been allowed in a gluten-free diet, but it has never been used in products manufactured and marketed as gluten free in the United States. Instead, U.S. gluten-free products are based on grains that are naturally gluten free. One food company in particular may have been responsible for this. In 1978, Ener-G Foods (originally a manufacturer of low-protein foods for people with kidney disease) brought one of the first—if not the first—gluten-free breads to market after being approached by Elaine Hartsook, dietitian and founder of the Gluten Intolerance Group. According to the Ener-G Foods website, Hartsook asked the company to make gluten-free bread for her patients with celiac disease but was adamant that it not contain any wheat starch. Ener-G Foods complied and thereby helped set the standard for gluten-free foods in the United States.

At present, in the United States, foods containing wheat starch are not recommended for people with celiac disease, and U.S. manufacturers of gluten-free foods do not use wheat starch in their products. However, this may be changing. Under the Food and Drug Administration's (FDA's) proposed rule on use of the term gluten free for labeling purposes, food labeled gluten free would be allowed to contain wheat starch as long as the gluten content of the final food product was less than 20 parts per million.

Wheat Starch and the Gluten-Free Diet

To understand the "wheat starch controversy," it is important to be familiar with the history of wheat starch and the gluten-free diet.

Beginning in the late 1930s, a Dutch pediatrician named Willem-Karel Dicke observed that his patients with celiac disease improved when they did not eat products containing wheat. In the late 1940s, he and his colleagues conducted feeding experiments designed to find out if wheat was the specific starch that caused problems for people with celiac disease. Patients participating in these feeding experiments were placed on diets that were similar except for the type of starch. Every few weeks, the specific starches provided to each patient were changed. Starches that caused a decrease in fat absorption and consequent increase in fat excretion were considered harmful to people with celiac disease. Based on these feeding experiments, Dicke and his colleagues found that while wheat flour had a harmful effect on their patients, wheat starch did not. Over time, however, concerns developed about the gluten content of wheat-starch-based "gluten-free" foods. Laboratory tests capable of detecting gluten confirmed that wheat-starch-based "gluten-free" foods contained small amounts of gluten.

In 2004 Finnish gastroenterologist Pekka Collin and colleagues tested twenty-six wheat-starch-based "gluten-free" flours and baked goods for gluten. Of these, only thirteen contained less than 20 parts per million of gluten (or 2 milligrams per 100 grams of product). Nine products contained between 20 parts per million and 100 parts per million of gluten, and two products contained between 100 parts per million and 200 parts per million. (For an explanation of the term parts per million, see "Science Class.") Whether or not these small amounts of gluten are harmful is at the heart of the wheat starch controversy.

Science Class

In simple terms, parts per million (abbreviated ppm) tells you how many parts out of a million are made up of the contaminant or ingredient in question. For example, suppose, for some reason, you want a million blue marbles. If you have a bag that contains a million marbles, and out of these million marbles, twenty are red and the rest blue, you could say your bag is "contaminated" with 20 parts per million of red marbles.

To use an example related to gluten-free eating, white bread has been reported to contain 124,000 parts per million of gluten. Assuming this amount is accurate, you can use this proportion to calculate that a one-ounce slice of white bread would contain 3,515 milligrams of gluten. Different varieties of wheat-starch-based "gluten-free" or "gluten-reduced" bread might contain 20 or 100 parts per million of gluten. One-ounce slices from each of these loaves would contain 0.6 milligram and 2.8 milligrams of gluten, respectively.

Codex Standard for Foods for Special Dietary Use for Persons Intolerant to Gluten

The Codex Standard for Foods for Special Dietary Use for Persons Intolerant to Gluten is one of the many standards established by the Codex Alimentarius Commission, a jointly run program of the Food and Agriculture Organization of the United Nations and the World Health Organization. The purpose of the commission is to develop universally accepted food standards, so that food producers around the world are meeting similar standards.

Codex standards are not legally binding in and of themselves. However, countries may choose to adopt them as their national standard. In the United States, the FDA's proposed rule for use of the term gluten free on food labels—that products labeled gluten free must contain less than 20 parts per million of gluten—is currently slightly stricter than the definition of gluten-free food contained in the Draft Revised Codex Standard for Foods for Special Dietary Use for Persons Intolerant to Gluten.

This Codex standard is still in draft form but is scheduled to be finalized in the summer of 2008. At the time this book went to press, the Draft Standard separates foods for special dietary use for persons intolerant to gluten into two categories: (1) gluten-free foods and (2) foods specially processed to reduce gluten content to a level above 20 up to 100 milligrams per kilogram. It is important to understand that Codex standards are not a labeling system per se. However, foods that are labeled gluten free or that have been processed to reduce gluten in countries that have adopted Codex standards as their national standard must comply with the following definitions:

Gluten-free foods

Specially manufactured foods that are made either from naturally gluten-free ingredients only—meaning foods made from rice, corn, etc., that naturally do not contain any gluten or from ingredients that naturally contain gluten, such as products made from wheat, barley, rye, or crossbred varieties of these grains but are rendered (or made) gluten free during processing. Gluten-free foods may contain no more than 20 milligrams per kilogram gluten (20 parts per million).

Foods specially processed to reduce gluten content to a level above 20 up to 100 milligrams per kilogram

Foods that are made from wheat, barley, rye, and crossbred varieties of these grains that have been specially processed to reduce gluten to a level above 20 up to 100 milligrams per kilogram (20 to 100 ppm of gluten).

In My Opinion

In my opinion, people with celiac disease should avoid wheat starch and products containing wheat starch that have been specially processed to reduce gluten to a level above 20 up to 100 milligrams per kilogram. However, if a manufacturer of wheat starch or products containing wheat starch demonstrates through testing that its products contain less than 20 parts per million of gluten (as currently proposed by the FDA), then in theory I support their consumption by people with celiac disease.

However, as a nutrition scientist, I believe it is important to point out that wheat starch is not a nutritious food product; it contains little or no fiber, vitamins, or minerals. There are so many healthful alternatives to wheat starch that I really see no need to start using it in gluten-free products. A gluten-free diet is likely to be more healthful without—rather than with—foods containing wheat starch.