The latest publication from the VITAL trial, authored by LeBoff et al., titled “Supplemental Vitamin D and Incident Fractures in Midlife and Older Adults” has gotten everyone talking again about vitamin D. Articles with headlines such as “Is Vitamin D Overrated? Another Study Casts Doubt on Benefits” and “Study Finds Another Condition That Vitamin D Pills Do Not Help” led to confusion and doubt about the use of vitamin D supplements. Responses from practitioners who have written to us since the publication and the publicity that followed included “now I get people saying that vitamin D does not work” – imagine the damage this might be causing to people’s health when their translation of the headlines leads to ideas such as this!

We know, beyond a doubt, that vitamin D is essential for our health. The “Totality of Evidence” provides the “whole-picture proof” that vitamin D can benefit our musculoskeletal, immune, cardiovascular, cognitive, and overall health, and reduces the risk of many diseases. Knowledge of human physiology has proven there is a demand for vitamin D within our cells for a multitude of every-day processes. Mechanistic studies have demonstrated how vitamin D works within the cells, tissues, organs, and the body as a whole to directly influence health and the development or regression of many skeletal and non-skeletal diseases. We see the effects of vitamin D demonstrated in observational and epidemiological studies over and over, with disease risk, prevalence, and outcome consistently related to vitamin D levels for many different types of diseases.

In the medical science world, randomized controlled trials (RCTs) are considered the “gold-standard” study design to provide solid evidence that “something works.” Since there has been so much evidence and research supporting the role of vitamin D in health, researchers took what they thought was the next logical step to further clarify if and how vitamin D did have an effect on certain health outcomes – they designed and executed RCTs for vitamin D. Unfortunately, while RCTs are efficient ways to evaluate the effects of a drug (something that is not present in the human body unless taken), the RCT design is often not the best-suited study for nutrients. The fact is that many randomized controlled trials of nutrient effects are poorly designed, a reason they can tend to lead to a finding of “no effect,” or a “null” result, when in fact, with a different design, the findings could have told a much different story.

To address issues arising from research such as this, Robert Heaney, MD, who spent much of his career doing research on vitamin D and other nutrients, developed and published a paper, “Guidelines for optimizing design and analysis of clinical studies of nutrient effects.” The table below lists the guidelines he recommended for optimum nutrient study design.

The above guidelines can be translated as follows to make them specific to vitamin D; ask yourself along the way if the vitamin D study you are questioning (such as the VITAL analysis on fracture risk) met the following criteria:

a) Measure vitamin D levels [as 25(OH)D] for all participants at the beginning of the trial (this is the baseline level or basal nutrient status)

b) Baseline levels should be an inclusion criterion for participating in the study, so that the study enrolls only those with beginning vitamin D levels below the response range for the disease outcome to be observed (typically below 20 ng/ml or 50 nmol/L for most diseases)

The intervention (whether it is supplementation, UVB exposure, or other) should include a sufficient dose of vitamin D to raise vitamin D levels among most treatment group participants into the therapeutic range (40-60 ng/ml or 100-150 nmol/L for many conditions)

Vitamin D levels must continue to be measured and recorded at time points during the trial, and at the end of the trial

a) The hypothesis should be that increased vitamin D levels into the therapeutic range (40-60 ng/ml for many conditions) will produce the specified effect (less disease, reduced symptoms, etc.)

b) The vitamin D level, not just the vitamin D dose, must be considered in the analysis

Co-nutrients for vitamin D should be optimized as well; for vitamin D studies, these would include calcium, K, and magnesium among others. (Calcium levels and urine calcium/creatinine levels can also be measured at the same time points as vitamin D levels for safety.)

Vitamin D RCTs should avoid bolus dosing (doses given monthly or longer). Vitamin D given on a daily or weekly basis (and in the form of vitamin D3) in doses the body can make from the sunshine (not much more than 25,000 – 50,000 IU at any given time) would better match how vitamin D is intended to be ‘received’ in our bodies. It is not possible to make 100,000 IU of vitamin D in a single day, and studies doing so are more likely to have negative findings.

It takes time to change nutrient levels within the body, and for that change to have an effect on disease status. For example, it can take up to 20 years for precancerous cells to develop into detectable cancer. A study that lasts only 3-5 years cannot conclusively determine that vitamin D supplementation does not prevent cancer. A study period less than or equal to 6 months of testing for chronic conditions and disease prevention could basically be considered useless.

In Parts 2 and 3 of this newsletter series, we will present a review of the VITAL trial design for its findings on fractures, according to the nutrient study criteria above, along with a detailed breakdown of WHY each criteria is essential to providing accurate and reliable study results, especially when it comes to vitamin D.

In the meantime… what do you think? Take a look at the paper with the criteria above in mind and ask yourself – did this study meet the Heaney nutrient study criteria?…

Don’t ever consider a situation too late to take steps for correcting or avoiding vitamin D deficiency. Measuring your vitamin D level and calculating a supplementation amount to help reach and maintain a target level, or taking loading doses to correct deficiency faster, could possibly make all the difference in how a current disease situation progresses. Test your level now!

Create your custom home blood spot kit, or choose one of our most popular:

Having and maintaining healthy vitamin D levels can help improve your health now and for your future. Choose which to measure, such as your vitamin D, omega-3s, and essential minerals including magnesium and zinc, by creating your custom home test kit today. Take steps to improve the status of each of these measurements to benefit your overall health. With measurement you can then determine how much is needed and steps to achieve your goals. You can also track your own intakes, symptoms and results to see what works best for YOU.

The eBook, Vitamin D & COVID-19, A Summary of Published Research, is a condensed and concise compilation of much of the published research on vitamin D and COVID-19, easy to read and share as a downloadable, printable PDF. Your purchase helps to further public knowledge and education of this invaluable research! Be sure to educate yourself on the benefits and importance of vitamin D for immune health, and take steps to ensure you and your loved ones are getting enough.

Don't get stuck with low vitamin D levels - learn more about what might affect your level and response to supplementation, and the steps to take through each season to keep levels in your target range.

Have a beautiful and HEALTHY day.

Onwards,