Phosphorus-Containing Food Additives and the Accuracy of Nutrient Databases: Implications for Renal Patients

Abstract

Objective-Phosphorus containing additives are increasingly added to food products. We sought to determine the potential impact of these additives. We focused on chicken products as an example.Methods-We purchased a variety of chicken products, prepared them according to package directions, and performed laboratory analyses to determine their actual phosphorus content. We used ESHA Food Processor SQL Software to determine the expected phosphorus content of each product.Results-Of 38 chicken products, 35 (92%) had phosphorus containing additives listed among their ingredients. For every category of chicken products containing additives, the actual phosphorus content was greater than the content expected from nutrient database. For example, actual phosphorus content exceeded expected phosphorus content by an average of 84 mg/100g for breaded breast strips. There was also a great deal of variation within each category. For example, the difference between actual and expected phosphorus content ranged from 59 to 165 mg/100g for breast patties. Two 100 g servings of additive containing products contain an average of 440 mg of phosphorus, or about half the total daily recommended intake for dialysis patients.Conclusion-Phosphorus containing additives significantly increase the amount of phosphorus in chicken products. Available nutrient databases do not reflect this higher phosphorus content, and the variation between similar products makes it impossible for patients and dietitians to accurately estimate phosphorus content. We recommend that dialysis patients limit their intake of additive containing products and that the phosphorus content of food products be included on nutrition facts labels.

Understanding Sources of Dietary Phosphorus in the Treatment of Patients with Chronic Kidney Disease

“…Indeed, it is believed that Ͼ90% of inorganic P may be absorbed in the intestinal tract, as opposed to only 40 to 60% of the organic P present in natural foods (51,52). The major public health implication from these considerations is that the P burden from inorganic P-containing food additives is disproportionately high relative to organic P. In the early 1990s, P additives contributed approximately 500 mg/d P to the American diet, whereas today P additives may contribute as much as 1000 mg/d P to the average American diet (37,51,53,54).…”

Assessing the Health Impact of Phosphorus in the Food Supply: Issues and Considerations

“…Several studies comparing estimated dietary phosphorus intake from nutrient databases with direct chemical analyses showed significant underestimation of phosphorus intake, suggesting inaccuracies in the nutrient content databases that serve as the basis for the dietary intake estimates shown in Table 3 ( [26][27][28][29]. This underestimation is presumably attributable to the failure to account for the use of phosphorus additives in processing.…”

Acute tumoral calcinosis due to severe hyperphosphatemia in a maintenance hemodialysis patient

“…Therefore, increased attention should be paid to the presence of food additives to avoid hyperphosphatemia due to the presence ? means no evaluation of excessive inorganic phosphates [15,16]. This is a public health problem, as disclosure of the phosphate content of foods is not currently mandated by public health authorities.…”