Energy Metabolism, Obesity
Conditions
Keywords
calcium carbonate, obesity, dairy, energy expenditure
Brief summary
Lifestyle choices,including diet,are conducive to healthy body weights in children. Dairy products and calcium supplementation have been associated with moderation of body weight and body fat. This study was designed to test the following hypotheses with overweight and obese adolescents consuming a controlled diet: * Dietary calcium supplementation as calcium carbonate or dairy calcium modulates energy balance in adolescents. * Increased calcium in the diet of adolescents will increase fecal fat excretion and thereby decrease fat absorption. * Calcium and dairy product supplementation will increase lipid oxidation resulting in an increase in energy expenditure.
Detailed description
Subjects will consume a controlled diet containing 800 mg calcium for two three week periods. During one period they will also receive a frozen ice cream like product (smoothie) twice a day based on soy protein that contains no additional calcium. During the other period they will receive a similar product twice a day based on either dairy protein that contains 650 mg calcium or based on soy protein that contains 650 mg calcium as calcium carbonate
Interventions
DIETARY_SUPPLEMENTC (smoothies based on soy protein containing no additional calcium)
Two smoothies per day based on soy protein containing no additional calcium
DIETARY_SUPPLEMENTB (smoothies based on soy protein containing calcium)
Two smoothies daily based on soy protein containing 650 mg calcium as calcium carbonate
DIETARY_SUPPLEMENTA (smoothies based on dairy protein containing calcium)
Two smoothies daily based on dairy protein containing 650 mg calcium
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Purdue University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
12 Years to 15 Years
Healthy volunteers
No
Inclusion criteria
* Over weight (\>85th percentile BMI for age)
Exclusion criteria
* \> 180% of ideal body weight for height * Malabsorptive disorders * Bone disease * Liver disease * Kidney disease * Anemia * Smoking or illegal drugs * Oral contraceptives * Pregnancy * Medications that influence calcium metabolism
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Energy balance will be calculated by quantitating the kilocalories represented by the following components: dietary intake, excreta, physical activity, resting energy expenditure, thermic effect of food, and thermogenesis. | After equilibration on a controlled diet for one week, measurements will be taken over an additional two week period. |
Secondary
| Measure | Time frame |
|---|---|
| Serum biochemical measures of calcium metabolism (PTH, Vitamin D, and calcium) | Serial meausures over a 10 hour period following a meal containing calcium from the placebo, dairy or calcium carbonate supplement |
| Calcium retention | Two weeks on a controlled diet following one week of equilibration on the same diet |
Countries
United States
Outcome results
None listed