Effect of calcium supplementation on iron bioavailability in women aged 35 to 45 years old
| ISRCTN | ISRCTN89888123 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN89888123 |
| Secondary identifying numbers | N/A |
- Submission date
- 03/06/2011
- Registration date
- 13/07/2011
- Last edited
- 23/05/2017
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Nutritional, Metabolic, Endocrine
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Plain English summary of protocol
Background and study aims
Iron is an essential nutrient involved in body processes such as red blood cell production and oxygen transport. Iron deficiency is a common nutritional disorder and the most common cause of anemia (a reduction in the number of red blood cells). Calcium is an essential mineral involved in growth. If the diet is not able to supply the body’s requirements, supplementation or fortification is a cost-effective alternative. Interactions between nutrients may increase the risk of nutritional deficiencies. For example, calcium may interfere with the body’s absorption of iron. The aim of this study is to determine the effect of calcium supplementation on iron absorption.
Who can participate?
Healthy women aged 35 to 45
What does the study involve?
Participants are randomly allocated to take three pills per day of either a calcium supplement or a placebo (dummy supplement). Blood samples are taken to measure the participants’ iron levels before and after the supplementation. Weight, height and dietary calcium and iron intake are also measured.
What are the possible benefits and risks of participating?
Not provided at time of registration
Where is the study run from?
University of Chile (Chile)
When is the study starting and how long is it expected to run for?
June 2011 to August 2011
Who is funding the study?
Chilean Science Council (Chile)
Who is the main contact?
Prof. Fernando Pizarro
fpizarro@inta.uchile.cl
Contact information
Prof Fernando Pizarro
Scientific
Scientific
Institute of Nutrition and Food Technology (INTA)
University of Chile
El Líbano 5540
Macul
Santiago
7830489
Chile
| fpizarro@inta.uchile.cl |
Study information
| Study design | Randomized controlled double-blind clinical trial |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised controlled trial |
| Study setting(s) | Hospital |
| Study type | Prevention |
| Participant information sheet | Not available in web format, please use the contact details to request a patient information sheet |
| Scientific title | A randomized controlled trial investigating the effect of calcium supplementation on iron bioavailability in women aged 35 to 45 years old in Santiago, Chile |
| Study objectives | 1. Heme iron bioavailability decreases after 43 days of calcium supplementation 2. Non-heme iron bioavailability decreases after 43 days of calcium supplementation Each participant was informed about the benefits, risks and reliability of the study through an informed consent. Participation was voluntary, remuneration was provided, and all subjects were free to withdraw at any stage of the study. Proceedings were done after reading and signed the written informed consent. |
| Ethics approval(s) | Ethics Committee at the Institute of Nutrition and Food Technology (INTA), University of Chile, 18/06/2008, ref: 13/200 |
| Health condition(s) or problem(s) studied | Iron bioavailability, iron-calcium interaction |
| Intervention | The target sample will consist of pre-menopausal women aged 35 to 45 years old, from the South East Area of Santiago Metropolitan Area, Chile. A group of 14 subjects supplemented with 600 mg of carbonate calcium will be compared with a control group (n = 14) receiving placebo. Participants will be randomly assigned to both groups. Follow up had a duration of 43 days. It was established that assessment of iron bioavailability and tracers of iron absorption that will be used are 55Fe and 59Fe radioisotopes. Iron absorption will be determined by Eakins and Brown double radioisotope technique. Additionally iron status, anthropometry and dietary micronutrient intake will be measured. Sample size calculation was 9 childbearing age women per group based on a difference of iron absorption of 5% between intervention and control group, with a statistical significance of 95% and a power of 80%. Considering a possible loss of the number of subjects it was decided to recruit 14 women per group, which corresponds to a total of 28. The intervention will last 58 days: Day 1: Blood sample of 10ml to measure iron status. Heme iron intake labeled with 111 kBq of 55Fe, intake recorded and anthropometry Day 2: Non heme iron intake labeled with 37 kBq 59Fe Day 14: Blood sample of 20 ml to measure circulating radioactivity (cpm/ml) Day 15: Beginning of supervised supplementation of carbonate calcium or placebo Day 45: Intake of heme iron labeled with 111 kBq of 55Fe Day 46: Intake of non heme iron intake labeled with 37 kBq of 59Fe Day 57: Ending period of supervised supplementation of carbonate calcium or placebo Day 58: Blood sample of 30 ml to measure circulating radioactivity (cpm/ml) and iron status Bioavailability: For the administration of non heme radioisotope 50ml of an aqueous solution containing 3mg of iron as ferrous sulfate labeled with 37 kBq of 59FeCl3 will be used. For the administration of the non heme radioisotope 2 capsules with dried sheep red blood cells with 3mg of heme iron intrinsically labeled with 111 kBq of 55Fe will be used. Using 20 ml of blood, circulating radioactivity will be measured in accordance with Eakins and Brown double radioisotope technique (1966). 55Fe and 59Fe (NEN, Life Science Products, Inc., Boston, MA) will be quadrupled. Iron status: 10 ml blood used to measure the following, hemoglobin (Hb), mean corpuscular volume (MCV) (CELL-DYN 1700, ABBOTT Diagnostics, Abbott Park, IL CEll Dyn), Zn protoporphyrin (Znpp) (Hematofluorometry ZP-M206D, AVIV Biomedical Inc., Lakewood, NJ). Serum ferritin (SF) by an enzyme immuno assay of double sandwich (INACG) Transferrin receptor (sTrF) and hepcidin by enzyme-linked immunosorbent assay (ELISA) (BioVendor, Laboratorní Medicína AS, Modrice, Czech Republic) Serum iron, total iron binding capacity (TIBC) and transferrin saturation (Fisher and Price) Anthropometry: Weight and height will be measured and compared with the patterns elaborated by World Health Organisation (WHO). Weight will be measured on a digital scale SECA ® with an accuracy of 0.1 kg, and length will be measured with a stadiometer of the same brand with an accuracy of 0.1 cm. 20. With these measurements body mass index (BMI) will be calculated as weight in kilograms divided by height (kg/m2). Weight and height will be used to determine blood volume using the table designated by Tulane Dietary calcium and iron daily intake: at the beginning of the study, three 24 hour recalls will be administered each time, on different days in order to estimate calcium and iron daily intake. Micronutrients calculation will be performed according to the recommended daily allowance (RDA) for childbearing age women (Food and Nutrition Board) |
| Intervention type | Supplement |
| Primary outcome measure | 1. Heme iron bioavailability 2. Non heme iron bioavailability |
| Secondary outcome measures | 1. Iron status 1.1. Hemoglobin 1.2. Mean corpuscular volume 1.3. Zn protoporphyrin 1.4. Serum ferritin 1.5. Total iron binding capacity 1.6. Serum Iron 1.7. Hepcidin 1.8. Transferrin Receptor 1.9. Transferrin Saturation 1.10. Total body iron 2. Nutritional state by anthropometry 3. Dietary calcium and iron daily intake |
| Overall study start date | 15/06/2011 |
| Completion date | 30/08/2011 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Adult |
| Sex | Female |
| Target number of participants | 28 women (14 will receive a calcium supplement and 14 a placebo) |
| Key inclusion criteria | 1. Apparently healthy women 2. Thirty five to 45 years old 3. Not participating in other clinical studies 4. Contraceptive use |
| Key exclusion criteria | 1. Morbidity (excepting anemia defined as hemoglobin < 120 g/L) 2. Daily use of medicaments 3. Pregnancy and pregnant interest (including a pregnancy test before the start of the study) 4. Breastfeeding 5. Iron and/or calcium supplementation 6. Postmenopausal women 7. Participation in previous studies particularly involving the administration of radioactive labeled iron 8. Smoking |
| Date of first enrolment | 15/06/2011 |
| Date of final enrolment | 30/08/2011 |
Locations
Countries of recruitment
- Chile
Study participating centre
University of Chile
Santiago
7830489
Chile
7830489
Chile
Sponsor information
University of Chile (Chile)
University/education
University/education
Institute of Nutrition and Food Technology (INTA)
El Líbano 5540
Macul
Santiago
7830489
Chile
| fpizarro@inta.uchile.cl | |
| Website | http://www.uchile.cl/ |
"ROR" |
https://ror.org/04teye511 |
Funders
Funder type
Research council
Fondo Nacional de Desarrollo Científico y Tecnológico (ref:1095038)
Government organisation / National government
Government organisation / National government
- Alternative name(s)
- National Fund for Scientific and Technological Development, El Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT
- Location
- Chile
Results and Publications
| Intention to publish date | |
|---|---|
| Individual participant data (IPD) Intention to share | No |
| IPD sharing plan summary | Not provided at time of registration |
| Publication and dissemination plan | Not provided at time of registration |
| IPD sharing plan |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Results article | results | 01/01/2014 | Yes | No |
Editorial Notes
23/05/2017: Plain English summary added.
