The Journal of Steroid Biochemistry and Molecular Biology, Volume 173, October 2017, Pages 265-272 https://doi.org/10.1016/j.jsbmb.2017.02.010
First presented at Vitamin D Workshop, March 2016
Taryn J.Smith, Susan A.Lanham-New, Kathryn H.Hart
- Vitamin D guidelines of American Academy of Pediatrics said none should be even tested, yet 91 percent had less than 30 ng – June 2017
- Many US kids have less than 40 ng of Vitamin D – 99 out of 100 blacks, 91 out of 100 whites – Jan 2017
- Takes a year to restore children and youths to good levels of vitamin D without loading dose - RCT Dec 2016
- Slow walking speed of youths 14 times more likely if low vitamin D - Dec 2016
- Youths need 1500 IU to get even 20 ng of vitamin D – RCT March 2016
- Is 50 ng of vitamin D too high, just right, or not enough
Most visited 10 pages in Youth category
- Adolescents are a population sub-group particularly vulnerable to low vitamin D status.
- Current intake recommendations of 10–15 μg/day may help avoid vitamin D deficiency (25(OH)D < 25–30 nmol/l).
- However higher intakes of 20–50 μg/day may be required to achieve adequacy (25(OH)D 50 nmol/l).
- Dose-response studies are needed to determine optimal 25(OH)D concentration for maximal bone accretion in adolescents and the intake requirements to achieve this.
Vitamin D is essential for bone development during adolescence and low vitamin D status during this critical period of growth may impact bone mineralization, potentially reducing peak bone mass and consequently increasing the risk of osteoporosis in adulthood. Therefore, the high prevalence of vitamin D inadequacy and deficiency in adolescent populations is of great concern. However, there is currently a lack of consensus on the 25-hydroxyvitamin D [25(OH)D] concentration, the widely accepted biomarker of vitamin D status, that defines adequacy, and the vitamin D intake requirements to maintain various 25(OH)D thresholds are not well established. While the current intake recommendations of 10–15 μg/day may be sufficient to prevent vitamin D deficiency (25(OH)D < 25–30 nmol/l), greater intakes may be needed to achieve the higher threshold levels proposed to represent adequacy (25(OH)D > 50 nmol/l). This review will address these concerns and consider if the current dietary recommendations for vitamin D in adolescents are sufficient.