Why should you take high doses of vitamin D?

A recent study has shown that the recommended daily dose for vitamin D should be 10 times higher than the present dose.

Both a recent publication in the Nutrients journal and research conducted by the renowned endocrinologist Robert Heaney have shown that the present recommendations as observed in traditional medicine have been based on a mathematical error. Furthermore, both works agree that the optimal values must be raised if we are to see any significant health benefits.

Neolife medical management

50% of people who take the recommended daily allowance (RDA) at present (600 units) do not reach the optimum minimum level for vitamin D.

The traditional medicine recommendation is a plasma vitamin D level (measured in the form of calcidiol or 25 OH cholecalciferol) of at least 20-30 ng/mL. The recommended daily dose so far is 600 to 800 iu (international units) per day, depending on the age of the person concerned. However, a recent publication in the Nutrients journal (1) has shown that the calculation upon which these doses are based is incorrect and so the target value of 20-30 ng/mL is also incorrect. If the calculation is incorrect as it has been asserted then the recommended daily dose of vitamin D is at least 10 times higher than previously imagined, that is to say we required 6,000 to 8,000 iu per day.

Endocrinologist Robert Heaney, Research Director at GrassrootsHealth (2), is one of the world’s leading researchers in vitamin D, most notably in respect of the dosage required to obtain certain health benefits. According to Heaney, the recommended daily dose of 20 ng/mL or more is clearly insufficient. He also highlights that the dose is defined as a “recommended daily dose” yet only 97.5% of the population are able to achieve the required amount each day. Scientific evidence to date has shown that at least 50% of those who take 600 iu of vitamin D are unable to achieve even 20 ng/mL. If we consider the correct calculation for a moment and the present proportion of the population that take the current recommended dose we discover that the daily dose would need to be raised to 7000 iu if the 97.5% success rate is to be maintained and we assume the population consumes at least 20 ng/mL or more per day. It is worth noting that half the required amount could be obtained by natural means (food and sunlight) and the other half could be consumed in the form of nutritional supplements.

Both the results of the study published in Nutrients journal and the research of Dr. Heaney agree that the recommended daily doses should be ten times higher than those we currently administer today. Unfortunately it is unlikely that the present official recommendations that were based on a mathematical error will be altered immediately and Dr. Heaney estimates that this could take about 10 years.

It should be noted that the discovered mathematical error was present in formulas used in studies carried out along or above the 50-north parallel.

Notwithstanding this it would appear that the above conclusion could foreseeably be applied to more southerly latitudes including the Spanish studies although further research is required to confirm this is the case.

On the other hand, both research studies believe that 20 ng/mL is too low to have a beneficial effect on health and that the recommended value should be raised to an amount greater than 40 ng/mL.

vitamin d well-being health benefits

What is the best time to start vitamin D supplementation? The sooner, the better.

Whilst the medical authorities decide whether or not to increase the recommended daily dose, at Neolife (a clinic which specializes in anti-ageing medicine), we prefer to act with diligence and promptness and not lose up to 10 years of disease prevention for vitamin D related diseases, which include, amongst others, colon cancer, breast cancer and osteoporosis.

To perform suitable vitamin D supplementation we must first determine the initial plasma levels of each person before establishing a personalized dose based on the aforementioned values from the tests. It is important to monitor the values continually in order to readjust the treatment as and when necessary.

Almost all of our clients present with levels that are below 30 ng/mL and many of them are below 20 ng/mL, so we prescribe them 5,000 ui a day for an initial 3-month period. After this period of time we then re-measure the values, which typically have reached levels above 60 ng/mL. At this point we readjust the dose in order to maintain a more permanent optimal value of ​​between 50 and 100 ng/mL.

Nutritional supplementation with vitamin D is completely safe; it is very rare for there to be any complications from toxicity, even at values ​​above 200 ng/mL.

It is never too late to start optimizing your vitamin D levels, but not too early either, given the consequences that result from vitamin deficiencies which present during childhood can follow though to adulthood and ultimately old age.


(1) Veugelers, P. J. and Ekwaru, J.P. “A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D”, Nutrients. 2014 Oct; 6(10): 4472-4475. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4210929/

(2) www.grassrootshealth.net