Impact of Food Additives on Phosphorus Metabolism
Impact of Food Additives on Phosphorus Metabolism
The purpose of the study is to learn more about how phosphorus-based food additives affect
 phosphorus metabolism in people with normal kidney function.
Phosphorus is a mineral that is found in foods such as dairy products, nuts, and meat, and is
 important for strengthening the bones. However, too much phosphorus in the blood may be bad
 for the health of your heart and blood vessels. The kidneys keep the blood levels of
 phosphorus normal by getting rid of extra phosphorus in the urine. New research has found
 that common forms of food additives that are high in phosphorus may increase blood phosphorus
 levels in individuals with kidney disease. In addition, these food additives may increase
 blood levels of hormones that control phosphorus such as parathyroid hormone (PTH) and
 fibroblast growth factor 23 (FGF23). Like high blood phosphorus levels, high levels of PTH
 and FGF23 in the blood may also be bad for the health of your heart and blood vessels. In
 this study, the investigators would like to examine the effects of food additives on blood
 levels of phosphorus, PTH and FGF23 in individuals with normal kidney function.
Inclusion Criteria:

 -  Healthy volunteers, 19 - 45 years of age

 Exclusion Criteria:

 -  abnormal urinalysis-presence of hematuria, proteinuria, or leukocyturia.

 -  pregnancy or breast-feeding

 -  Medical conditions impacting phosphate metabolism-primary hyperparathyroidism;
 gastrointestinal malabsorption disorders such as Crohn's Disease, ulcerative colitis,
 celiac disease, or liver dysfunction; hyper- or hypothyroidism; irregular menses for
 female subjects.

 -  Body Mass Index (BMI) ≥ 30 g/m2 since obesity is independently associated with
 impaired phosphorus metabolism.

 -  Medications known to affect phosphorus metabolism- current use of phosphorus
 supplements, high-dose or activated vitamin D compounds, regular antacid or laxative
 use, anticonvulsants.

 -  Hyper- or hypophosphatemia (≥ 4.6 mg/dl or ≤ 2.5 mg/dl respectively), hyper- or
 hypocalcemia (≥ 10.6 or ≤ 8.5 mg/dl respectively), or severe anemia (hemoglobin < 8
 g/dl for women and < 9 g/dl for men).