Low-sodium lunch meats often contain extra potassium

(Reuters Health) - People who need to avoid potassium in their diets because of kidney disease or other health issues may want to steer clear of reduced-sodium sandwich meats, researchers say.

The Canadian study team found that sodium-reduced packaged chicken and meat slices in supermarkets contained an average of 44 percent more potassium than their regular counterparts, largely because of potassium-containing additives in the low-sodium products, according to the report in the Journal of the Academy of Nutrition and Dietetics.

“As a result of the health effort to reduce the sodium content of processed foods, there are more sodium-reduced packaged foods appearing on grocery shelves,” said senior study author Pauline Darling of the University of Ottawa.

Food manufacturers sometimes use potassium and phosphorous with additives to replace the sodium flavor, she said, but the amounts are often not listed on food labels. Patients with chronic kidney disease, in particular, are advised to eat diets low in sodium, phosphorous and potassium.

“It is unclear if sodium-reduced foods are safe for patients with chronic kidney disease or for those who are taking blood pressure medications,” Darling told Reuters Health by email.

The researchers chemically analyzed 19 original and 19 sodium-reduced meat and poultry products from the top three grocery chains in Canada, measuring the protein, sodium, phosphorous and potassium in each one. A product was considered sodium-reduced if the label advertised it as having at least 25 percent less sodium than the original version.

The study team found that, on average, low-sodium products contained 38 percent less sodium than their original versions. They also contained an average of 184 milligrams (0.01 oz) more potassium. Total potassium ranged from 210 mg to 1500 mg per 100 grams (3.53 oz) of meat. A food considered to be high-potassium is one that contains more than 200 mg per serving, the authors note.

“On average, the higher amount of potassium contained in the sodium-reduced meat and poultry products was equivalent to an extra serving of a high-potassium food,” Darling added.

Additives containing potassium were found on the ingredient list in 63 percent of the sodium-reduced products, as compared to 26 percent of the original versions. Phosphorous and protein didn’t differ significantly between the two groups of products, however.

Future studies should look at the harms and risks of sodium versus potassium-recommended diets for people with kidney or heart problems, said Dr. Kamyar Kalantar-Zadeh of the University of California, Irvine School of Medicine, who wasn’t involved in the study.

“In the efforts to reduce the sodium content of food, we may avoid one harm and end up with another harm,” he told Reuters Health by phone. “It’s a good example that in our ongoing quest to reduce sodium, we may inadvertently cause more problems.”

Potassium can help lower blood pressure, but for those with kidney disease, high potassium can be tough for the body to process.

“Although this study suggests that low-sodium foods are higher in potassium, what we really need to know is whether it makes a difference in real-world situations,” said Dr. Orlando Gutierrez of the University of Alabama at Birmingham Nutrition Obesity Research Center, who also wasn’t involved in the study.

“If it doesn’t, then the issue is academically interesting but practically not of much value,” he told Reuters Health by email.

Potassium content should be included on food labels, especially for sodium-reduced products, so consumers can make better choices about their diet, the study authors write.

“These patients need to be cautious about sodium-reduced meat and poultry products,” Darling said. “It would be best for them to choose fresh meat and poultry with no additives.”

SOURCE: Journal of the Academy of Nutrition and Dietetics, online January 6, 2018.