Here’s a big list of studies about vitamin D and child development:
Linking Vitamin D Status, Executive Functioning and Self-Perceived Mental Health in Adolescents Through Multivariate Analysis: A Randomized Double-Blind Placebo Control Trial (2017)
Conclusion: A randomized double-blind placebo-controlled trial involving 50 Norwegian adolescents found that those given vitamin D supplements performed better on cognitive tests compared to the placebo group.
Conclusion: A study of 85 Philadelphia children found that those with lower vitamin D levels have worse insulin resistance.
A 16-Week Randomized Clinical Trial of 2000 International Units Daily Vitamin D3 Supplementation in Black Youth: 25-Hydroxyvitamin D, Adiposity, and Arterial Stiffness (2010)
Conclusion: A 4-month study of 44 black teenagers found that 95% had low vitamin D levels and that supplementing with 2,000 IU of vitamin D daily was effective for reducing arterial stiffness and increasing vitamin D levels. The study also found that the vitamin D levels of the obese subjects rose less than the leaner subjects. Although 2,000 IU daily was effective in raising levels, only 56% achieved sufficient levels after the four months.
Conclusion: Adolescent girls with higher vitamin D levels are able to jump faster and higher compared to girls with lower vitamin D levels.
Low Vitamin D Status Has an Adverse Influence on Bone Mass, Bone Turnover, and Muscle Strength in Chinese Adolescent Girls (2009)
Conclusion: In a study of 301 young Chinese girls, those with the higher vitamin D levels demonstrated superior handgrip strength and had higher bone mass.
Prevalence and Associations of 25-Hydroxyvitamin D Deficiency in US Children: NHANES 2001-2004 (2009)
Conclusion: A 3-year study of 9,757 U.S. children and young people found that: 61% had low vitamin D levels, those who spent more time watching/using TVs and computers had lower vitamin D levels, obese children had lower vitamin D levels, and those with lower vitamin D levels had higher blood pressure.
Conclusion: 40 mother-baby pairs were tested for vitamin D deficiency. 50% of the mothers and 65% of the babies were deficient. There is a strong correlation between maternal vitamin D levels and vitamin D levels of newborn infants.
High Prevalence of Vitamin D Insufficiency in Black and White Pregnant Women Residing in the Northern United States and Their Neonates (2007)
Conclusion: A study of pregnant women in Pittsburgh found that roughly 50% of them, and later their babies, were vitamin D insufficient.
Conclusion: Obese children were found to have lower vitamin D levels than non-obese children. In the obese children, losing weight resulted in an increase of their vitamin D levels.
Maternal Intake of Vitamin D During Pregnancy and Risk of Recurrent Wheeze in Children At 3 y of Age (2007)
Conclusion: 1194 mother-child pairs in Massachusetts were analyzed. It was found three years later that the children from mothers with the highest vitamin D intake during pregnancy had the lowest risk of developing recurrent wheezing.
Effect of Vitamin D Replacement on Musculoskeletal Parameters in School Children: A Randomized Controlled Trial (2006)
Conclusion: For a one-year period, 179 girls ages 10-17 were given either a weekly placebo, low dose of vitamin D, or higher dose of vitamin D. After one year the girls given the higher dose of vitamin D showed the biggest increase in lean muscle mass and bone density, especially among the younger girls.
Prospective Study Of Maternal Intake Of Vitamin D During Pregnancy And Risk Of Wheezing Illnesses In Children At Age 2 Years (2006)
Conclusion: 1,306 mother-child pairs were analyzed and it was found that higher “maternal vitamin D intake was associated with lower childhood risks of any wheeze” or asthmatic symptoms in their child by age two.
Conclusion: 78% of unsupplemented babies in the study became vitamin D deficient during winter.
Conclusion: Vitamin D deficiency was observed in 11 out of 23 young Maine girls who were part of a six-month study. The study also found that the mean vitamin D level dropped 28% during winter.
Vitamin D Deficiency and Whole-Body and Femur Bone Mass Relative to Weight in Healthy Newborns (2005)
Conclusion: In a study of 50 healthy mothers and their newborns, nearly half were classified as being vitamin D-deficient and newborns with lower vitamin D levels also were found to have lower bone density.
Vitamin D Requirements During Lactation: High-Dose Maternal Supplementation as Therapy to Prevent Hypovitaminosis D for Both the Mother and the Nursing Infant (2004)
Conclusion: This randomized control trial found that breastfeeding mothers need at least 4,000 IU of vitamin D daily to ensure their breastfeeding infants are getting enough vitamin D.
Conclusion: Vitamin D-deficient mothers have vitamin D-deficient breast milk, putting their newborns at a high risk of vitamin D deficiency.
Conclusion: In a study of 307 Boston teenagers, it was found that 42% had vitamin D blood levels 20 ng/ml or below, 24% had levels of 15 ng/ml or below, and 4.6% were severely deficient with levels of 8 ng/ml or below. The study also found vitamin D levels to be 24% lower in the winter compared to summer.
A Systematic Review and Meta-Analysis of Northern Hemisphere Season of Birth Studies in Schizophrenia (2003)
Conclusion: Schizophrenics tend to be born more in winter and spring compared to other seasons, when vitamin D-creating UVB radiation is less available. They also tend to be born more in latitudes farther away from the equator, which get less UVB radiation.
Conclusion: “Low levels of maternal vitamin D may be associated with an increased risk of schizophrenia.”
Association of Low 25-Hydroxyvitamin D Concentrations with Elevated Parathyroid Hormone Concentrations and Low Cortical Bone Density in Early Pubertal and Prepubertal Finnish Girls (2003)
Conclusion: A study of 193 young Finnish girls found that those with vitamin D-deficiency had lower bone density.
Vitamin D and Attainment of Peak Bone Mass Among Peripubertal Finnish Girls: A 3-y Prospective Study (2002)
Conclusion: A 3-year study of 171 young, healthy Finnish girls found that the girls with lower vitamin D levels also had weaker bones.
Effects of Vitamin D Metabolites on Intestinal Calcium Absorption and Bone Turnover in Elderly Women (2002)
Conclusion: A study of vitamin D and bone mineral density levels in young Finnish girls found that those with lower vitamin D levels also had lower bone density.
Wintertime Vitamin D Deficiency in Male Adolescents: Effect on Parathyroid Function and Response to Vitamin D3 Supplements (2001)
Conclusion: A study of French male teenagers found that the majority of the test subjects were very deficient in vitamin D.
Conclusion: 30 cases of infant and childhood nutritional rickets in North Carolina were analyzed. 100% of the patients were dark-skinned, had been breast-fed an average of 12 months, and did not receive vitamin D supplements prior to their rickets diagnoses. Dark-skinned people tend to have disproportionately lower vitamin D levels due to the melanin in their skin blocking UVB solar radiation necessary for vitamin D synthesis. Babies who are breastfed by vitamin D-deficient mothers without receiving vitamin D supplements tend to develop even more severe vitamin D deficiencies than their mothers.
Mild Mental Retardation in Black and White Children in Metropolitan Atlanta: A Case-Control Study (1995)
Conclusion: This study of 893 children in Atlanta, Georgia, U.S. (330 mildly retarded kids and 563 normal controls) found that the rate of mental retardation in black children is nearly double that of white children. Although this study did not explore vitamin D as a factor, it is proven and well-documented that vitamin D is a crucial factor in brain development in utero and during childhood and there is also an overwhelming amount of evidence that blacks disproportionately suffer from vitamin D-deficiency and vitamin D-deficiency-related diseases and disorders due to the high amount of melanin in their skin partially or totally preventing cutaneous vitamin D synthesis from sunlight. It is also well-documented that people with mental disabilities and mental disorders tend to have lower vitamin D levels or have been born from and breastfed by mothers with poor vitamin D levels, and that vitamin D plays a very large role in producing optimal cognitive performance throughout life.
Conclusion: Hip fracture rates for newborns reach their peak January-February and occur least July-August. These rates are in correlation with seasonal vitamin D level changes. Adequate vitamin D is essential for bone strength.
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