Please select the eligibility criteria that correspond to the clinical trial below.
Title: N/A
Brief Summary: Vitamin D has a range of biological effects of public health relevance. Vitamin D status is assessed on levels of its metabolite 25-hydroxyvitamin D \[25(OH)D\], where levels \< 50 nmol/L indicate insufficiency. Despite studies indicating that the vitamin D intake among Swedish children are significantly below recommendations, little is known of their vitamin D status. The investigators have recently found inadequate vitamin D status in pre-school children living in northern Sweden, especially in dark-skinned children and during the winter months despite vitamin D intakes meeting the recommendations. Overall, 25% of the light skinned and 40% of the dark skinned children had S-25(OH) D \<50 nmol/L (Öhlund I, unpublished data). The aim is to examine which amount of vitamin D is needed to maintain or increase S-25(OH)D to ≥50 nmol/L among 97.5% of the participants regardless of skin color or geographic location (northern or southern Sweden). Furthermore the investigators will examine if vitamin D status affects on health markers as bone density, blood pressure, serum lipids, fatty acids, inflammatory and immunological markers and mental wellbeing.

Children aged 5-8 years living either northern (Umeå) or southern Sweden (Malmö) will be recruited to this trial during November-December 2012. They will be randomized to a vitamin D supplement of either 10 or 25 g per day, or in Malmö also placebo to be used for three months. The randomization will be stratified according to skin color (light or dark) according to a method using visual inspection and interviews of parents/guardians. The investigators will use a 2×2×2 factorial design to investigate the effects of two different doses of vitamin D (10 µg and 25 µg) in children with dark and light skin color, living in northern (Umeå) and southern (Malmö), Sweden. In order to achieve a moderate difference between groups (effect size 0.25) 20 children per group are required (power\> 87%, alpha = 0.05). With an estimated dropout of 10%, a total of 220 children will be included.

At baseline, the participants will undergo blood sampling for S-25(OH)D and other biomarkers, blood pressure and anthropometrical measurements, including bone densitometry and body composition using air displacement pletysmography, and the parents will answer a questionnaire on behavioral and emotional problems in the participating child using the Child Behavior Checklist. These measurements will be repeated at follow-up in February-March 2013.


Options:
A: Inclusion Criteria:

1. mothers presenting with active dental decay or restorations within the past year (high caries risk)
2. mothers who are the primary caregivers for their child
3. healthy children without systemic disease aged 6 months to two years
4. Infants younger than 6 months who have one or more teeth present

Exclusion Criteria:

1. mother or child with systemic disease
2. antibiotics or medications taken within the previous 3 months that may alter oral flora and saliva flow for mother or child
3. children who primarily receive care in a daycare center or by a caregiver other than the mother
B: Inclusion Criteria:

* Pregnant (week 26 or earlier)
* At least 15 years of age
* Medicaid eligible
* Speaks English
* Willing and able to comply with study instructions
* Mother AND child available for length of the study (\~ 24 months)

Exclusion Criteria:

-
C: Inclusion Criteria:

* Lives in a selected cluster
* Is \>= 6 months pregnant
* Has no plans to move outside of the cluster within 1 year

Exclusion Criteria:

* Reduced ability to collaborate for psychological/mental reasons
* Severely ill
* Has given birth more than 7 days ago
* Has given birth less than 7 days ago and it was a multiple birth; or the child has a severe malformation; or death of the mother or the baby.
D: Inclusion Criteria:

* 5-7 years of age
* Healthy

Exclusion Criteria:

* Chronic illness, including coeliac disease or other chronic gastrointestinal disorders
* Drugs that can affect bone health or vitamin D uptake
* Cow's milk allergy

Answer: D