Vitamin D mistake (John Campbell)

A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D (2014)

US, nearly 15 times too low

UK, 0ver 22 times too low

IOM calculation

600 units (15 mcg), 97.5% of people will achieve
63 nmol/L

(25.2 ng/ml)

Correct calculation

600 units (15 mcg), 97.5% of people will achieve 26.8 nmol/L

(10.7 ng/ml)

Requirements based on correct calculation

8,895 IU of vitamin D per day may be needed to accomplish that 97.5% of individuals achieve serum 25(OH)D values of 50 nmol/L or more.
The "Average" vs. "Individual" Mistake



[Posted at the SpookyWeather2 blog, December 9, 2025.]