The Food and Nutrition Board of the Institute of Medicine has not been upstanding and forthright with the American people regarding vitamin D needs. This situation is even worse in the UK, but let’s focus on the egregious behavior of the US officials only. Here is the process of setting a Recommended Dietary Allowance (RDA):
Notice how the RDA is set to be two standard deviations above the Estimated Average Requirement (EAR) for persons. When set there, it is expected to cover the needs of approximately 97.5% of individuals, while being insufficient to meet the needs of the last 2.5% of people — the needs of that last 2.5% of people are ignored by officials.
Here is an idealized distribution of vitamin needs for a given vitamin, along with a vertical line where the RDA would be set, at 2 standard deviations above the mean, and therefore at the [97.5]th percentile:
Only those with the highest 2.5% of needs have their needs unmet by the RDA.
Even though 2.5% of people are left out in the cold like that, ignored by public policy, there is a trade-off which must be made and it is thought to be a reasonable policy if you can develop recommendations which really do work out for 97.5% of the people. It is sometimes thought that serving the needs of 100% of the people is unrealistic.
But when it comes to setting the RDA for vitamin D, is the Food and Nutrition Board even accomplishing the more modest task of really and truly covering the needs of 97.5% of Americans?
A “College Freshman”-level Mistake
As it turns out, when the RDA for vitamin D was set, a statistical mistake was made. It’s one that is pretty rudimentary and might be thought of as a mistake that a college freshman in Statistics might make.
Instead of compiling data on the individual needs of individual persons, and chosing the [97.5]th percentile value, the Food and Nutrition Board erroneously compiled data on the mean values from groups of people, and chose the [97.5]th percentile of the mean values for the RDA.
Let’s show what that process looks like, with two simple samples of individual needs, all in International Units (IU) required in order for individuals to reach an already-too-low target value of 20 ng/mL (50 nmol/L) of active vitamin D (of 25-hydroxyvitamin D):
Sample 1: (302, 393, 485, 578, 639, 753, 888) ← mean is 577
Sample 2: (312, 423, 525, 618, 709, 803, 908) ← mean is 614
Notice how there is not much variation in these sample means, although there is more variation in the individual values (the individual vitamin D needs). If 1,000 of such samples were taken, and of those 1,000 sample means, the sample mean that was higher than 975 of them would become the [97.5]th percentile value.
But notice how, applied to just the 7 values in each of these two samples (14 total values), there is a great chance that the top 3 of every 7 people would have their needs unmet by an RDA which got set by using sample means instead of individual values.
Taking the 14 people of these two samples together, a proper RDA would not be anywhere near the 614 value (the higher of the means), but instead it would meet the needs of at least 13 (92.8%) of the 14 of them — it would need to be at least 888 or more.
And that would have been just to make it to an already-low target value of active vitamin D which only serves to help with musculoskeletal needs. Even higher amounts of vitamin D have been shown to help with immunity, for instance.
So, not only is the estimation process rigged so as to give answers that are too low by definition (means vs. individual values), but even the logic utilized in setting the RDA (focus on musculoskeletal system only) was set without optimizing human health in the first place.
Error Pointed Out 10 Years Ago
The most disturbing aspect of the official stance on vitamin D is not that an error was made, but that — even 10 full years after the error was pointed out — there has not been an official retraction of original estimates and an update which incorporates the real needs of human beings.
Because of not increasing the RDA for vitamin D immensely, government officials appear to be operating under perverse incentives, such as those of the “disease industry” (pharmaceutical firms that rely on high prevalence of disease for profits). People need to realize that a large portion of disease stems from poor nutrition.
But officials seem to be playing into the hands of Big Pharma when they set recommendations which are statistically guaranteed to be insufficient for maintaining human health and resistance to infection for 97.5% of us — like they are supposed to. They have the gall to think that they can continue to get away with it.
But it keeps us sick and it keeps Big Pharma rich.
Reference
Veugelers PJ, Ekwaru JP. A statistical error in the estimation of the recommended dietary allowance for vitamin D. Nutrients. 2014 Oct 20;6(10):4472-5. doi: 10.3390/nu6104472. PMID: 25333201; PMCID: PMC4210929. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4210929/
“The correct interpretation of the lower prediction limit is that 97.5% of study averages are predicted to have values exceeding this limit. This is essentially different from the IOM’s conclusion that 97.5% of individuals will have values exceeding the lower prediction limit.”
Heaney R, Garland C, Baggerly C, French C, Gorham E. Letter to Veugelers, P.J. and Ekwaru, J.P., A statistical error in the estimation of the recommended dietary allowance for vitamin D. Nutrients 2014, 6, 4472-4475; doi:10.3390/nu6104472. Nutrients. 2015 Mar 10;7(3):1688-90. doi: 10.3390/nu7031688. PMID: 25763527; PMCID: PMC4377874. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4377874/
“Since an RDA, by definition, relates to intake from all sources, it is clear that total intake required to achieve 20 ng/mL in 97.5% of the cohort must be close to 7000 IU per day, not substantially different from that calculated by Veugelers and Ekwaru.”
Papadimitriou DT. The Big Vitamin D Mistake. J Prev Med Public Health. 2017 Jul;50(4):278-281. doi: 10.3961/jpmph.16.111. Epub 2017 May 10. PMID: 28768407; PMCID: PMC5541280. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541280/