Calcium Metabolism in Mexican American Adolescents
|Osteoporosis||Dietary Supplement: Low Calcium Diet Dietary Supplement: High Calcium Diet|
|Study Design:||Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
|Official Title:||Calcium Metabolism in Mexican American Adolescents|
- Calcium Absorption and Retention [ Time Frame: June 2010-July 2010 ]
- Bone Density [ Time Frame: June 2010-July 2010 ]
|Study Start Date:||April 2010|
|Study Completion Date:||August 2010|
|Primary Completion Date:||August 2010 (Final data collection date for primary outcome measure)|
|Active Comparator: Low Calcium Diet (600-1200 mg/d)||
Dietary Supplement: Low Calcium Diet
The basal diet will contain 600 mg of Ca per day and constant sufficient amounts of all other nutrients. Additional Ca will be given unfortified beverages served three times per day. Teens will be randomized to a lower (600-1200 mg/d)level of calcium in the first camp followed by the opposite (higher calcium diet)regime in the second camp.
|Active Comparator: High Calcium Diet (1100-2300mg/d)||
Dietary Supplement: High Calcium Diet
The basal diet will contain 600 mg of Ca per day and constant sufficient amounts of all other nutrients. Additional Ca will be given unfortified beverages served three times per day. Teens will be randomized to a higher (1100-2300mg/d)level of calcium in the first camp followed by the opposite (lower calcium diet)regime in the second camp.
Previously significant racial and sex differences in calcium retention and kinetics in adolescents has been found. Other minority groups have increased calcium absorption efficiency at low calcium intakes in contrast to white adolescents. Since Hispanics and specifically Mexican Americans will soon comprise an increasing proportion of our population. We propose to identify calcium metabolism characteristics in this group. We predict that calcium requirements to maximize bone health in this population will be lower than for white youth but higher than their current intakes.
Thus the specific aims of this project include:
- to establish calcium requirements
- to establish the relationship between calcium intake and calcium absorption
- to identify the major physiological parameters(kidney, intestine, bone) that contribute to calcium retention in Mexican-American adolescents
During this two-phase metabolic camp participants will consume either a higher calcium diet(1100-2300mg/d) or a lower calcium diet (600-1200mg/d) during the first 3-week phase and switch to the opposite regime during the second 3-week phase, with a 2-week washout period in between. Subjects will collect all excreta during both phases. Calcium absorption, height, weight, and bone density will evaluated throughout the 6-week period of the study.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01277185
|United States, Indiana|
|West Lafayette, Indiana, United States, 47907|
|Principal Investigator:||Connie Weaver, PhD||Purdue University|
|Study Director:||Berdine Martin, PhD||Purdue University|