Clinical trial NCT01394146: Impact of Food Additives on Phosphorus Metabolism
Official title: Impact of Food Additives on Phosphorus Metabolism
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: phosphorus-based food additives
phosphorus metabolism
Lead sponsor: University of Alabama at Birmingham
Sponsor class: OTHER
First posted: 2011-07-14
Enrollment: 54
Sex: ALL
Minimum age (years): 19
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP

Brief summary: The purpose of the study is to learn more about how phosphorus-based food additives affect phosphorus metabolism in people with normal kidney function.

Detailed description: 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.

Eligibility criteria: 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).

Primary outcomes:
measure: FGF23
timeFrame: 2 weeks
measure: PTH
timeFrame: 2 weeks
measure: Serum phosphate
timeFrame: 2 weeks
Secondary outcomes:
measure: Insulin sensitivity as measured by HOMA-IR
timeFrame: 2 weeks
measure: Brachial flow mediated dilatation measured by ultrasound
timeFrame: 2 weeks
Other outcomes:
Locations:
city: Birmingham
country: United States
facility: University of Alabama
state: Alabama
Study officials:
affiliation: University of Alabama at Birmingham
name: Orlando M Gutierrez, MD, MMSc
role: PRINCIPAL_INVESTIGATOR
References:
citation: Gutierrez OM, Porter AK, Viggeswarapu M, Roberts JL, Beck GR Jr. Effects of phosphorus and calcium to phosphorus consumption ratio on mineral metabolism and cardiometabolic health. J Nutr Biochem. 2020 Jun;80:108374. doi: 10.1016/j.jnutbio.2020.108374. Epub 2020 Mar 19.
citation: Gutierrez OM, Luzuriaga-McPherson A, Lin Y, Gilbert LC, Ha SW, Beck GR Jr. Impact of Phosphorus-Based Food Additives on Bone and Mineral Metabolism. J Clin Endocrinol Metab. 2015 Nov;100(11):4264-71. doi: 10.1210/jc.2015-2279. Epub 2015 Aug 31.