DEAR DR. BLONZ: Is there any problem with drinking salty soup? Our son has developed a taste for ramen and craves some every day. We know it's high in fat and salt, but since he is 14 and not overweight, should we be concerned about those issues? For a while he was using only half the flavoring packet, but lately he seems to want it saltier. What do you think? -- A.H., Watertown, Wis.

DEAR A.H.: It is not unusual for children and adolescents to develop preferences that oftentimes border on cravings. Regardless of how you try to instill balance in their diets, they insist on their favorites and you begin to wonder if they are getting the nourishment they need. Ramen-type soups provide convenience and a reliable flavor, and the flavoring packets of some brands can be high in sodium. Most, however, are relatively modest in fat.

Because there is brand-to-brand variety, you might be able to find an acceptable soup with better nutritional attributes. If he is stuck on a particular brand that offers little besides noodles and salty soup, I would take solace in the fact that your son will be eating other foods during the day and that they probably don't follow the same format. Another potential fix would be to give an OK on the ramen, but see if he would be amenable to adding some peas, corn or other vegetables to the soup. Perhaps you could strike a deal where points from the consumption of other "balancing" foods would have to be earned before the ramen is given the green light. In the end, keep in mind that these types of desires tend to pass with time.

DEAR DR. BLONZ: I recently bought packages of fish fillets that contained farm-raised catfish. When I got home, I noticed that the fish contained ingredients that I am questioning, especially since I watch my salt intake. They include sodium tripolyphosate, sodium hexametaphosate, acid pyrophosate, citric acid and salt. Since when is salt put on frozen fish fillets? All those sodium compounds sound like a no-no for a person with high blood pressure. I hate to toss them, but since I read the ingredients, I have lost my appetite for them. I would appreciate your help. -- J.P. Carlsbad, Calif.

DEAR J.P.: Chemical names can sound intimidating. A fresh or fresh-frozen fish wouldn't be using these additives, but the product wouldn't have much of a shelf life. As for your ingredients, the first four are there to help maintain quality of the product during its shelf life. They are often referred to as sequestrants: To put it simply, they keep the elements involved in spoilage reactions away from each other. This has the net effect of delaying the breakdown that makes food go bad. Although it may not be what you had intended on purchasing, there is no evidence that these compounds are harmful, and having them is certainly preferable to consuming a product that has begun to spoil.

There would only be minimal sodium supplied by these ingredients, as they are only there in very small amounts. Salt is added for flavor, and the amount added would depend on the manufacturer. If this is a packaged, processed fish fillet, the Nutrition Facts label will provide the total amount of sodium per serving, regardless of source.

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.

DEAR DR. BLONZ: I have a severe reaction to shellfish like crab and lobster, but eating shrimp doesn't bother me at all. My question relates to scallops: I want to be able to eat them, but am unsure if I can do so safely. The nutritionist I consult with said that my allergy was probably due to iodine, but I am not sure how this could be the case. -- S.I., San Jose, Calif.

DEAR S.I.: While some people may react to iodine, that is usually only when it's applied in large amounts as a disinfectant, as in surgery or other medical procedures. The typical shellfish allergy is not due to the presence of iodine. Iodine is an essential mineral needed by the body to make the thyroid hormone. It is found in most seafood, and is also present in foods made with iodized salt, which includes many restaurant foods.

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.

Rather than iodine, allergies to shellfish -- including clams, crabs, lobster, oysters, shrimp and scallops -- tend to be caused by a protein found in the shellfish. It is unusual that you would tolerate shrimp when crab and lobster set you off. Because scallops are in that shellfish group, I suggest you refrain from any experimentation -- especially because you classify your reaction as "severe." What you need to do is to speak with your physician -- not a nutritionist -- and undergo a standard allergy test conducted by an allergist. In these tests, you will be exposed to very diluted extracts of shellfish, along with other substances that may be suspect. The test is done in a safe, controlled setting.

DEAR DR. BLONZ: I have been advised to seek a holistic medical doctor who uses a technique called "muscle testing" to determine which nutritional supplements I should be taking. In this type of testing, the doctor places supplements under my tongue. Then, while I am on my back, he has me raise my right leg about 10 inches. If he can press my leg down, he recommends that the 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? -- B.R., Coolidge, Ariz.

DEAR B.R.: My opinion is that this test is questionable to say the least. I have never found any evidence to support the reliability of such a technique. I would approach with caution any other advice from the individual who told you to seek such stuff.

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.

DEAR DR. BLONZ: If blood glucose level is so important -- if it gets too low, we get weak or pass out -- why does the body automatically convert the carbohydrates we eat into fat? Why don't we store carbs like we do fat? -- R.S., Dublin, Calif.

DEAR R.S.: Plants are able to capture energy from the sun, photosynthesizing the sun's energy into carbohydrate using carbon dioxide from the atmosphere. The human body, like that of most other animals, can't do this. Our only source of energy comes from the foods we consume.

Fat gets used as the storage form because it is nature's most concentrated form of metabolic energy, containing over twice the energy per unit weight as proteins or carbohydrates such as glucose. A concentrated form of energy is essential for us because of mobility: If we stored the bulk of our energy as carbohydrate, we would be too bulky to move.

That provides a good contrast to plants, where the basic theme is staying put, sending roots into the soil for nutrients and growing leaves that are exposed to the sun. With sunshine comes more energy for growth, the production of flowers, and the eventual production of seeds for the next generation. Plants take in their "meal" of sunshine and convert their energy into carbohydrate because it takes up the most space per calorie, which then speeds their growth.

Although the "mission" of the plant is to grow rapidly while remaining in one spot, that of the seed is very different. A seed must be light enough to be carried by the wind or on the fur of animals, but after falling to the ground, it needs to have enough stored energy to fuel the process of sending out roots and growing shoots. Seeds' need for concentrated energy explains why they store their enery as fat, as opposed to carbohydrates like mature plants.

You asked about carbohydrate storage in our body. It turns out that there is a small amount in the form of glycogen, which is a branched chain of glucose molecules. Glycogen is stored in the liver and muscles. It gets used as a source of emergency muscle energy, or if the blood sugar level drops too low, but it's not a large amount: The average adult has just over 100 grams in the liver and about 250 grams in all the muscles combined.

DEAR DR. BLONZ: Why should you only take 500 milligrams of calcium at a time? My supplement contains 600 milligrams and I had been taking two at bedtime. I had heard that it is better to take them at bedtime, but now I hear differently. Could you please comment? -- S.A., Seattle

DEAR S.A.: The reason for the calcium limit is that the efficiency of absorption tends to decrease when a single dose exceeds 500 milligrams. Taking larger amounts means that more will end up passing through without being absorbed. It is probably wise to find a way to distribute your calcium in more than one dose, and taking it at mealtime is usually best.

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.