On Nutrition by Ed Blonz

Iodine Unlikely Culprit for Allergic Reaction

DEAR DR. BLONZ: I have an allergy to crab and lobster, due to the iodine. Shrimp doesn't bother me at all, but my big question is whether scallops fall into the crab/lobster category or into the shrimp category. I have wanted to enjoy these tender morsels for a long time, but am cautious, due to my fears of a potential heart-stopping reaction. -- J.B. Seattle, Washington

DEAR J.B.: The typical shellfish allergy is not due to the presence of iodine. Some people may react to iodine, but usually only when there is inadvertent exposure to large amounts, such as with a disinfectant used in surgery or other medical procedures. Iodine is an essential mineral needed by the body to synthesize its thyroid hormone, which is involved with the regulation of our metabolism. This mineral is found in most seafood, but it is also present in foods made with iodized salt -- including most foods served in restaurants.

When there is insufficient iodine, the thyroid gland, which is located in the throat, becomes enlarged and the condition referred to as "goiter" results. Goiter used to be common in the Great Lakes regions of the United States, but the condition was virtually eliminated following the addition of iodine to table salt in 1924.

Shellfish allergies tend to relate to a sensitivity to the protein found in shellfish. The shellfish family includes clams, crabs, lobsters, oysters, shrimp and scallops. Specific food allergies are possible, but it is unusual that one would be able to tolerate shrimp when crab and lobster set them off. Because scallops are in the shellfish group, it would be best to refrain from any experimentation -- especially if there is a risk of a "heart-stopping" reaction. The prudent approach would be to consult with an M.D. allergist. He or she can determine if it would be appropriate to give you an allergy test where you'd be exposed to very dilute extracts of the fish in a controlled, safe setting. Stay well.

DEAR DR. BLONZ: I am seeing a holistic medical doctor who relies heavily on a technique called "muscle testing" to determine which nutritional supplements I should be taking. The supplements are placed under my tongue, and then, while I am on my back, he has me raise my right leg about 10 inches (while the pill is still under my tongue). If he can press my leg down, he recommends that supplement be taken. If he cannot force my leg back down on the table, he says I don't need the supplement. What is your opinion of this technique? -- C.B., Los Angeles

DEAR C.B.: This test is dubious, to say the least. I have never found any evidence to support the reliability of such a technique. If it were me, I would find another doctor.

Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.