IFAC Statement on “Effect of Neighborhood Food Environment and Socioeconomic Status on Serum Phosphorus Level for Patients on Chronic Dialysis”
In November 2020, the study titled “Effect of Neighborhood Food Environment and Socioeconomic Status on Serum Phosphorus Level for Patients on Chronic Dialysis” was published in the Journal of the American Society of Nephrology. The authors reviewed data on patients receiving dialysis and the availability of food in their neighborhoods to determine whether greater access to “healthy” food affected on phosphorus levels in the patients. While it was surmised that patients living in geographical areas with more poverty, which the authors suggest have higher amounts of foods containing high levels of phosphorus and are, in their words, “unhealthy,” the authors found no link between phosphorus levels and neighborhood food availability or income. Based on findings that older patients had lower serum phosphorus levels than younger patients, and that patients who identify as Black or Hispanic had slightly lower phosphorus levels than white patients, the authors suggest phosphorus levels may be better managed through personalized diet plans and improved education regarding food labels. An accompanying article in Nephrology News & Issues contains a perspective on the study by Lisa Gutekunst, a renal dietitian, who noted there were no insights into specific foods being purchased or where patients bought food, and that the fact that stores sell “healthy” food does not mean they contain lower levels of phosphorus or that patients purchase them.
While the above information seems to call into question the health aspects of phosphorus, research supported by the International Food Additives Council (IFAC) has found dietary phosphorus, including phosphate food additives, are not a concern for most people. Research led by Dr. Victor Fulgoni explored the National Health and Nutrition Examination Survey (NHANES), a study which assesses the health and nutritional status of Americans, and intake of foods containing phosphorus. Dr. Fulgoni reviewed data collected from 1988 to 2016, specifically identifying intake levels of foods and beverages containing naturally occurring phosphorus as well as phosphorus that would be added through phosphate food additives. He found that the majority of phosphate intake in the U.S. diet comes from naturally occurring phosphorus, with the top three most common phosphorus-containing foods for adults (+19 years of age) being coffee, yeast breads, and cheese. Only about 12% of phosphorus intake came from added phosphates. These findings show that foods that generally contain higher levels of naturally occurring phosphorus are not necessarily unhealthy and that greater emphasis on the labeling of foods containing phosphate additives is unlikely to have a meaningful impact on phosphorus intake.
While those with chronic kidney disease (CKD) or end stage renal disease (ESRD) should be conscious of their phosphorus intake, the general population should not be concerned about their phosphate intake and potential health risks. The outcome of a 2017 review of 110 primary research articles on dietary phosphorus and human health found no conclusive evidence of phosphate consumption and negative health outcomes in the general population. Phosphate intake recommendations for the general population and those with CKD or ESRD is further explained by Dr. Taylor Wallace in a webinar conducted in March 2020. More information on the webinar can be found here.
For individuals looking to monitor their phosphorus intake, phosphate food additives are included on the ingredient list of all foods and beverages. Although companies are not required to disclose the amount of phosphorus on the Nutrition Facts panel, some volunteer this information and share the amount of phosphorus or other nutrients. Others list detailed product information on their websites if it is not on the label.