San Diego, CA; Omaha, NE—According to researchers, the National Academy of Sciences (NAS) Institute of Medicine’s (IOM) Recommended Daily Allowance (RDA) of Vitamin D is only one-tenth of what is necessary to prevent conditions related to vitamin D deficiency.
The IOM currently suggests an intake of 600 IU per day for those ages one to 70 and 800 IU per day for those that are older. Robert Heaney, M.D. of Creighton University asserts that the IOM needs to change this value to at least 7,000 IU per day in order to accurately inform the public. Experts are concerned that this calculation error will have serious implications for disease prevention and bone health.
The IOM calculated this RDA from data collected from 10 studies where subject’s levels of 25-hydroxyvitamin D (25(OH)D) were measured. From the 32 computed averages, the IOM estimated that 600 IU of vitamin D per day would result in a 25(OH)D level of 56 nmol/L. Accounting for experimental error, the IOM believes 600 IU vitamin D would result in 50 nmol/L 25(OH)D in 97.5% of the population.
Those who dispute this value, however, found an error in the interpretation of the figures. Using the data that the IOM collected, they calculated that 600 IU per day of Vitamin D would only produce 26.8 nmol/L of 25(OH)D, not 50 nmol/L. To produce 50 nmol/L of 25(OH)D, a person would have to absorb 8,895 IU of vitamin D per day.
The effects of this incorrect value are already apparent. A study conducted in Canada found that of those who consumed an average of 232 IU per day in their diet and then supplemented 400 IU, 10% had less than the necessary 50 nmol/L of 25(OH)D. In a second study, 15% of participants were under this level. According to experts, if the IOM’s RDA were correct, less than 2.5% of the participants should have had deficiencies.
Published in WholeFoods Magazine, May 2015