DEAR DR. BLONZ: In a package of catfish filets I purchased, I noticed a number of ingredients of concern, given that I need to limit my intake of sodium. These include sodium tripolyphosphate, sodium hexametaphosphate, acid pyrophosphate, citric acid and salt. Since when is salt put on frozen fish filets? All those sodium compounds sound like a no-no for a person who has high blood pressure, such as myself. I hate to toss them, but since reading the ingredients, I have lost my appetite for them. -- H.T., San Diego
DEAR H.T.: 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 the ingredients on your list, the first four are there to help maintain the quality of the product during its shelf life. To put it simply, there are chemical reactions that take place during spoilage, and these compounds keep the elements involved in these reactions away from each other. They are referred to as "sequestrants" because they "sequester," or keep substances from mingling and reacting together, with the net effect of delaying the food going "bad." Although it may not be what you had intended on purchasing, there is no evidence that these compounds are harmful; 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. This being a package of a processed fish filets, there should be a Nutrition Facts panel on the label that will reveal the total amount of sodium per serving, regardless of source. Use that as your guide. In the future, be sure to read the label completely before you buy.
DEAR DR. BLONZ: I'm a constant reader of your column and appreciate your practical approach to nutrition questions. In an issue of Women's Health, I read that brown rice contains arsenic, and that when boiled, it leaches out but then is reabsorbed. They recommended cooking brown rice in a coffeemaker: pouring water into it and letting it run through. Secondly, a doctor on PBS claimed that tuna has toxins, so it should be avoided. I'm in the habit of having brown-rice sushi with salmon or tuna, plus avocado, at least a couple of times a week. Is that harmful? Am I consuming arsenic and/or toxins? -- K.L., via email
DEAR K.L.: I periodically enjoy tuna and certainly have not sworn off rice -- especially brown rice. Granted, arsenic has a rather intimidating persona, but there are issues relating to the type and level of consumption. Read a more detailed perspective on arsenic in rice at tinyurl.com/lboa7gv.
As regards tuna, much depends on where and how it is caught. Read the review at tinyurl.com/hwmtfrt. (Note: These two articles are from the Berkeley Wellness Letter from the University of California, Berkeley. I serve on the editorial board of this newsletter.)
Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to email@example.com. Due to the volume of mail, personal replies cannot be provided.