Please select the eligibility criteria that correspond to the clinical trial below.
Title: Evaluation of Calcium, Vitamin D, Magnesium, and Zinc Absorption in Healthy Children 4 to 8 Years of Age
Brief Summary: The goal of our research is to provide data to enhance the development of nutritional guidelines, especially as related to mineral nutrition, in children. Using human experimentation, we are studying methods of delivering the key minerals of calcium, zinc and iron in the diet so as to optimize health outcomes. We will conduct a controlled trial of vitamin D supplementation to assess the effects of vitamin D status on calcium absorption in small children. We will evaluate the effects of differing intakes of zinc on zinc and copper absorption. These studies will utilize stable isotope techniques so as to provide accurate, practically applicable information which may be obtained from the study populations in a safe manner. These data will have global application and provide a strong basis for evidence-based nutritional recommendations to be developed.

Objective #1: To evaluate the effects of supplemental vitamin D in enhancing calcium absorption in healthy children 4 to 8 yrs of age.

Objective #2: Assess the absorption of magnesium and zinc in healthy children 4 to 8 yrs of age.


Options:
A: Inclusion Criteria:

* Delivery at \> or = 35.0 weeks gestation with birth weight \> or = 2.5 kg
* BMI: 10th - 90th percentile for age and gender
* Ages 4.0 to 8.9 years
* Ethnic distribution of greater Houston area
* Usual calcium intake 600-1200 mg/d based on two 24-hour dietary recalls by phone
* Any regularly taken (daily) vitamins and minerals must be stopped at least 1 month before starting the study

Exclusion Criteria:

* History of any chronic illness.
* Regularly taken (daily) medications (except seasonal allergies).
* Avoidance of dairy products or meat in the diet.
B: Inclusion Criteria:

* Age 1-5 years
* Physician-diagnosed asthma (as per the 2015 Canadian Position Paper on the diagnosis of preschool asthma)
* ≥1 asthma exacerbation requiring rescue oral corticosteroids (OCS) in the past 6 months or ≥2 in the past 12 months (as documented by pharmacy/medical records)
* ≥4 upper respiratory tract infections (URTIs) in the past 12 months (as per parental report)
* URTIs as the main asthma trigger (as per parental report)

Exclusion Criteria:

* Intake \> 400 IU/day of vitamin D3 supplements or fish oil in the past 3 months
* Intention to use \> 400 IU/day of vitamin D3 supplements or fish oil in the fall and winter
* Extreme prematurity (\< 28 week gestation)
* No vitamin D supplementation (if breast-fed in the last 6 months)
* Vitamin D restrictive diets, that is, minimal intake of vitamin D fortified milk (\<250 mL/day for 1-3 years or \<375 mL/day for 4-6 years AND no other (or \<200 IU/day) vitamin D supplement
* Recent immigrants from regions at high risk of rickets (in the past 12 months)
* Recent refugees (in the past 12 months)
* Undernourished children
* Other chronic respiratory disease (e.g. Cystic fibrosis, Bronchopulmonary dysplasia) or chronic kidney, gastrointestinal, endocrinological or cardiac diseases, or sickle cell anemia?
* History of bone disorder disease (e.g. rickets, osteomalacia)
* Intake of oral anti-epileptic, diuretic or anti-fungal medications
* Anticipated difficulty with follow-up or with adherence to the intervention or the procedures
C: Inclusion Criteria:

* Male and female adults of all races ages 18 years and older

Exclusion Criteria:

* 1. Pregnant and lactating women.

  2. Current or recent history of hepatic or renal disease

  3. History of taking a daily supplement that contains more than 400 IU vitamin D2 or vitamin D3 within the past month or taking a pharmacologic amount of vitamin D2 or one of the active vitamin D analogs including Zemplar (Paricalcitol), Dovonex (calcipotriol), Hectorol (vitamin D pro hormone)

  4. Subjects who are taking antiseizure medications or glucocorticoids.

  5. Exposure to a tanning bed or tanning on a beach for more than eight hours within the past month.

  6. Known history of elevated calcium. (\> 10.5 mg% (mg/dl))

  7. History of intestinal malabsorption (i.e. Cystic Fibrosis, Fat Malabsorption Syndrome, Crohn's Disease)

  8. Unwilling to consent to this trial
D: Inclusion Criteria:

* children aged 1-5 years
* physician-diagnosed asthma as per GINA guidelines
* upper respiratory tract infections as the main asthma exacerbation trigger
* ≥4 respiratory infections in the past 12 months
* ≥1 exacerbation requiring rescue oral steroids in the past 6 months or ≥2 in the previous 12 months.

Exclusion Criteria:

* extreme prematurity (\<28 weeks gestation)
* infants \<12 months of age
* breastfed infants with no vitamin D supplementation
* recent (\<1 year) immigrants from countries where rickets and malnutrition prevalent
* other chronic respiratory disease (broncho-pulmonary dysplasia; cystic fibrosis)
* endocrine disorder of calcium/ vitamin D metabolism
* disorder/ disease with associated malabsorption (inflammatory bowel disease)
* kidney/ liver disease
* sickle cell anemia
* medications known to interfere with bone metabolism/ vitamin D levels
* vitamin D supplementation \>1000 IU/ day in past 3 months
* unable to attend medical visit in 3-4 months
* plan to leave the province during the next 6 months.

Answer: A