Potassium additives may make low-sodium meats unsafe for patients with kidney disease

Sodium-reduced foods are becoming increasingly available to consumers; however food manufacturers may use phosphate and potassium additives to replace the functional and flavor properties of sodium. Because individuals with kidney dysfunction must maintain diets low in phosphorus and potassium, it's unclear if sodium-reduced foods are safe for patients with kidney disease.

Arti Sharma Parpia, RD (St. Michael's Hospital, in Toronto) and her colleagues analyzed 19 sodium-reduced meat and poultry products from the main grocery store chains in Canada, noting the products' protein, sodium, phosphorus, and potassium content compared with the original meat products that were not low in sodium.

Among the major findings: • Sodium-reduced meat and poultry products contained 25% to 55% less sodium than their non-sodium-reduced counterparts. • The potassium content of sodium-reduced products ranged from 210 to 1500 mg/100g and was significantly higher than non-sodium-reduced products by 195 mg/100g. • Potassium-containing additives were found on the ingredient list in 63% of the sodium-reduced products and 25% of the non-sodium-reduced products. • The amounts of phosphorus did not differ significantly between the 2 groups.

Parpia noted that 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. "Patients with chronic kidney disease need to be aware of the potential for higher potassium content in sodium-reduced foods, as they are educated to follow a low sodium diet and may inadvertently choose sodium-reduced foods without realizing the risk of an increased potassium load from additives," she said. "This research supports the mandatory inclusion of potassium content on nutrition fact tables, especially on product labels that claim to be reduced in sodium."