Is salad a no-no?

[Jimbo1968]

Just to be clear my mother who has been diagnosed with MC nearly 10 years ago no longer adheres to a gluten free diet but she will avoid lettuce like the plague. Your post actually caught my interest because I found it difficult to believe originally in my mums case but it is true

[tex]

Do you suppose it could be contaminated from the source of the flour?

Yes, the biggest risk for flour is cross-contamination during milling, because it's virtually impossible to perfectly clean grain conveying equipment and stone mills. (I'm speaking from experience here — I was in the food corn processing business for years.) Therefore, unless the miller uses a dedicated line for GF flours, there is always an overlap when product runs occur. They clean the equipment as best they can, and throw away the first flour that is milled, but there is always a risk of a clump of wheat flour that was stuck in some corner coming lose and falling into a GF flour batch. Good milling equipment is expensive, and demand for quantities of certain GF flours is typically too low to justify the cost of a dedicated production line. Therefore, various types of flour are typically produced on the same line. Most of the run will be safe (below 20 ppm), but there will almost always be some lots that will have enough cross-contamination to exceed tolerance limits. And since the FDA assumes that non-gluten grains are pure, no testing is required, to assure purity. In fact, a few years ago, the FDA was trying to adopt a regulation that would have forced processors to label any flour or products made from non-gluten grains as GF. Most processors are well aware that grains assumed to be "pure" are not always pure, so they fought that regulation.

My colleagues (Anne Lee, Schar, USA and Thomas Grace, Bia Diagnostics) and I recently published findings from a pilot study on grain contamination in the June issue of the Journal of the American Dietetic Association (Thompson T, Lee AR, Grace T. Gluten Contamination of Grains, Seeds, and Flours in the United States: A Pilot Study. J Am Diet Assoc. 2010;110:937-940). What follows is a summary of study findings.

Bottom line: Seven of 22 (32%) samples tested contained mean gluten levels above 20 ppm with amounts ranging from 25 to 2,925 ppm.

The red emphasis is mine, of course.

The following products contained above the limit of quantification for gluten:

Product/Mean ppm
Millet flour/305
Millet flour/327
Millet grain/14
Millet grain/25
White rice flour/8.5
Buckwheat flour/65
Sorghum flour/234
Soy flour/2,925
Soy flour/92

The following products tested below the limit of quantification for gluten: basmati rice; long grain brown rice; enriched corn meal; instant polenta; 1 sample of rice flour; hulled buckwheat; buckwheat groats; amaranth flour; flax seed; and amaranth seed.

Contamination of naturally gluten-free grains

These levels of contamination typically will not make every celiac sick, at least not immediately. But the effect of the damage done to the small intestine tends to be cumulative, so that if one eats such products regularly, problems eventually develop. And unfortunately, there are a few of us who are sensitive enough to certain foods that these levels will cause us to promptly react (within a few hours). Tests show that many people who are sensitive to gluten typically react to levels that exceed 50 ppm. And a small percentage of us react to contamination levels below 10 ppm. The legal limit in most of the world is 20 ppm, but some countries (such as Australia) enforce a maximum contamination level of 10 ppm for gluten.

Unfortunately, most "health experts" tend to overlook this glaring problem with our food system.

Tex