Institute Of Medicine Vitamin D

Abstract

There is still controversy about the amount of vitamin D adults need for musculoskeletal health. The Endocrine Society, which made its recommendations for the treatment and prevention of vitamin D deficiency, concluded that to guarantee bone health without any evidence for vitamin D deficiency osteomalacia, a blood level of 25(OH)D of at least 75 nmol/L (30 ng/mL) was required for adults. As a result the Endocrine Society recommended that for adults 1500–2000 IU/day was required for musculoskeletal health and noted that obese adults require 2–3 times more vitamin D to sustain a blood level of 25(OH)D of at least 75 nmol/L. The more conservative recommendation from the Institutes of Medicine (IOM) is the recommended dietary allowance (RDA) for vitamin D, 600 IU/day (15 μg/day), which the IOM claims sustains 97.5% of the population with serum 25(OH)D above the threshold of 50 nmol/L (20 ng/mL). We show how the IOM made incorrect analyses of the evidence it cited, thereby severely underestimating the serum 25(OH)D threshold. Furthermore, to calculate the intake of vitamin D needed to deliver the threshold serum level, the IOM used group average serum 25(OH)D responses to establish the vitamin D RDA. Because half of a population needs more than the average, the 600 IU/day RDA for vitamin D underestimates the intake needed to assure the threshold for 97.5% of the population. For people who are sun-deprived or with darker skin at temperate latitudes, the 600 IU/day RDA cannot assure the threshold serum level. The IOM specified 4000 IU/day for most children and adults to the safe, upper level for vitamin D, whereas the Endocrine Society specified 4000 IU/day for most children and 10,000 IU/day for adults. Although the IOM did not base its 50 nmol/L (20 ng/mL) threshold for serum 25(OH)D for musculoskeletal health on randomized clinical trials (RCTs), advocates of the IOM position now reject the normal criteria for evidence-based decisions and demand that RCTs are needed for acceptance of any extraskeletal health relationship. We contend that it is unrealistic to ever expect that RCTs can be conducted for vitamin D in the long-term primary prevention of disease events in a healthy adult population under age 50 years. The existing prospective, cross-sectional, and clinical trial evidence for mortality and premature delivery in pregnancy is already enough to warrant further increases in recommendations for vitamin D supplementation.

Keywords

Bone mineral density

Dietary guidelines

Dosing interval

Endocrine society

Enzyme kinetics

Evidence-based medicine

Extraskeletal benefits of vitamin D

Fractures

Institutes of medicine

Medical care

Nutrition

Osteomalacia

Public health

Randomized clinical trials

RDA

Recommended dietary allowance

U-shaped risk curves

Vitamin D

Institute Of Medicine Vitamin D

Source: https://www.sciencedirect.com/science/article/pii/B9780128099650000598

Institute Of Medicine Vitamin D