Food Additives Council Speaks Out on Dietary Phosphorus
The International Food Additives Council (IFAC) is an international association representing companies that produce high quality substances used globally as food additives and food ingredients. IFAC is responding to an article published in the December 2012 issue of Food Technology, “Is Dietary Phosphorus a New Health Target?,” by Clemens et al., which suggests that dietary phosphorus intake needs to be further scrutinized for potential human health impacts.
None of the evidence cited in the article demonstrates a direct link between dietary phosphate intake and negative health outcomes in healthy populations. Even in populations with compromised kidney function, including chronic kidney disease (CKD), no definitive link is established between serum levels of phosphorus and renal function or cardiovascular disease. Because of the potential for this article to unnecessarily raise concern about dietary phosphate intake, IFAC would like to provide some additional information that your readership may find relevant.
It is well documented that phosphorus is an essential nutrient, critically important for every cell of the body, as it is involved in cell signaling, bone formation, and acid-base regulation. It is important to understand that the predominant mineral in bones is hydroxyapatite, a compound that includes both calcium and phosphorus. The presence of both calcium and phosphorus is essential for growth and maintenance of healthy bones.
Furthermore, inorganic phosphates have a long history of safe use as food ingredients. For decades, numerous toxicology studies have examined the safety of phosphate-based food additives. These toxicological studies have been reviewed by several panels of internationally recognized experts, including the Joint FAO/WHO Expert Committee on Food Additives and the Select Committee on GRAS Substances (SCOGS). These scientific evaluations form the basis upon which worldwide regulatory approval has been granted to phosphate-based food additives. Phosphates have also undergone numerous additional reviews by international regulatory authorities, including the U.S. Food and Drug Administration and the European Food Safety Authority, and the Codex Alimentarius Commission has adopted numerous provisions (categories of use and use levels) for phosphate-based food additives.
Seriously ill patients on life-sustaining dialysis referenced in Clemens et al. are not able to properly metabolize and eliminate excess levels of various food components, including phosphorus. Further, it is not scientifically credible to think that a minor alteration of the diet alone, such as reducing phosphate consumption, would be effective in preventing a disease like CKD, which is known to be multifactorial. Furthermore, calcium status and pharmacological treatment of these patients, among other factors, need to be considered. Humans require a certain level of dietary phosphate for proper functioning of body systems, and any phosphorus consumed in foods beyond what the body needs is excreted from the body in individuals not affected by CKD or similar serious diseases.
While the article suggests that only a small percentage of the American public consumes less than the recommended amount of phosphorus, the authors overlook the fact that certain populations in the U.S. do not consume enough phosphorus on a daily basis. Estimates of usual intakes of phosphorus derived by the Institute of Medicine show a significant proportion of the U.S. population may not be meeting the Reference Daily Intake levels for phosphorus (Institute of Medicine, 1997).
As a group, phosphates comprise one of the most important functional segments of food ingredients. These high-quality ingredients are used to enhance the characteristics, cooking performance, and value of the foods in which they are used. In addition, phosphates can improve the nutritional value of foods, an important benefit to increasing numbers of health-conscious consumers.
The safety of phosphates for healthy individuals is well supported by the scientific literature, and to misrepresent this science-based information is a disservice to your readers.
Response from author Roger Clemens, Dr.P.H., Food Technology Contributing Editor, Chief Scientific Officer, Horn Company:
The biological importance of phosphorus is evident, and the safety of phosphate-containing food additives is unmistakable. The most recent NHANES data (2009–2010) indicate the majority of the U.S. population consumes nearly twice the Recommended Dietary Allowance (RDA) for this nutrient without any associated adverse events. This same data set indicates a small percentage of the American public consumes less than the Estimated Average Requirement (EAR). Important to the risk of chronic kidney disease (CKD), a phosphorus intake of 1033 +/- 382 mg/day among those with moderate CKD as defined by eGFR (estimated glomerular filtration rate) does not appear to be associated with increased risk of mortality (HR: 0.93–1.03; Murtaugh et al., 2012).
On the other hand, other publications also cited in the December 2012 article suggest dietary phosphates may represent an emerging concern among those patients with renal disease. As with many food and health topics, the evidence on dietary phosphorus and its impact on CKD appear to be inconsistent. It is important, however, to note that none of the scientific publications suggest a causal relationship between dietary phosphorus, phosphate-containing food additives, and CKD.
References cited are available from the authors.
—Haley Curtis Stevens, Ph.D.,