Poor randomized clinical trial results are maligning these key supplements
SEVENTY-FIVE PERCENT OF AMERICANS TAKE SUPPLEMENTS, 78% of whom are 55 years of age and older. Couple that with continued supplement sales growth of more than 6% per year.
The market for vitamin D alone is expected to reach $2.5 billion in North America by 2020.¹ Omega-3s remain hugely popular, with sales of $2.29 billion in 2018 and expected to grow 7.4% per year over the next several years — in large part attributable to prescriptions. This, despite daily reports on the ineffectiveness of both omega-3 and vitamin D, and many other popular vitamins and minerals. The entire industry, and the practitioners who support it, is under constant fire to demonstrate why nutrients sometimes can’t be obtained from food, and to prove how supplements improve health status. How can you know if your patients are benefiting from the supplements they take? Fortunately, there’s a study for that.
Practitioners rely on sound data to support their work. It can be awkward to read meta-analysis after meta-analysis on how omega-3 and vitamin D fail to live up to claims, and still recommend the most obvious of nutritional supplementation for a population woefully deficient in both.
This is not the fault of the nutrient, but rather the rate limiting use of our presumed scientific “gold standard” — randomized clinical trials (RCTs), which in their current construct will always fail scientific analysis of vitamins and minerals.
Randomized clinical trials
RCTs are ideal for measuring safety and efficacy standards of pharmacologic intervention since you are introducing a foreign object (drug) into the body. Not so for the more complex nutrients that exist in the body, consumed through food and supplementation, with intricate and healthy interactions that always warrant additional study. In addition, all nutrients are efficacious. The appropriate scientific question is: For what are they effective and at what level?
Herein lies the problem. Virtually all nutrient RCTs are focused on the assigned study dose, overlooking the level of the nutrient in your body.
The impact of such a significant oversight is illustrated, and broadly publicized, through the meta-analysis of RCT nutrient research, the most often-used tool to discredit the effectiveness of nutrients.
In the words of the late Robert P. Heaney, MD, distinguished professor of medicine and world-renowned researcher, “Randomized trials usually cannot — and, I stress, cannot — provide the evidence needed to ground nutrient health claims or nutrient intake recommendations. As a result, progress cannot be made until the policy establishment accepts this fact and agrees upon alternatives to RCTs.”
Heaney asserted harmonization of RCTs is futile unless the selected studies use the same, or similar, dosing; use the same chemical form of the nutrient; optimize the same co-nutrients; and be measured for the same duration. Instead, the meta-analyses are marketed to news outlets as evidence that people who are not nutrient-deficient do not need supplementation, when in fact nutrient level has not been documented or evaluated.
In 2011, the Institutes of Medicine concluded that a recommended dietary allowance for vitamin D of 600 IUs for adults will ensure 97.5% of the age group achieves a serum level of 20 ng/ml. 2 Ergo, virtually all RCTs on vitamin D are based on study participants taking 600 IUs per day, and fail to measure the associated serum levels. We cannot know the therapeutic impact of vitamin D without knowing vitamin D blood serum levels. The answer lies not with the RCT model, but the use of nutrient field trials.
This is where the Organic & Natural Health Association, in partnership with GrassrootsHealth, an international nonprofit research organization, is focusing its research efforts and our work to support practitioners and individuals in their quest to reduce nutrient deficiency and improve health status.
In the field
Nutrient field trials are high-powered observational studies, carefully and rigorously designed, conducted and evaluated to demonstrate correlations between nutrients and health outcomes while taking into consideration the multiple actions and interaction of nutrients. Founded in 2007, GrassrootsHealth has documented that a serum level of at least 40-60 ng/ml is required to reap the health benefits of vitamin D. We now know higher vitamin D serum levels reduce pre-term births by 60%, among other significant findings.
Organic & Natural Health joined forces with GrassrootsHealth and its 17,000 cohort to conduct a two-year nutrient field trial on omega-3 oil and vitamin D. Experts assert that achieving an omega-3 index of 8-12% is required to reap the full health benefits of EPA and DHA. The majority of the U.S. population is woefully deficient, with levels at or below 4%. Our objective was to determine what is required to achieve effective omega-3 levels, and what associated health benefits are derived from achieving optimal levels.
Approximately 1,200 people enrolled in this first phase of our study, with roughly 500 submitting at least two blood spot tests to measure their levels. All study participants completed a lengthy survey providing data on dose consumed, foods eaten, health issues and health outcomes. The median age of study participants was 59. Sixty percent were female and 93% white, residing in 27 countries worldwide, approximately 95% of whom resided in the United States or Canada. Here’s what we learned:
Utilization — Omega-3 utilization was scattered across a host of products (493) representing 236 brands. Seventeen percent of study enrollees took two or more omega-3 supplements, with 2% taking three or more. Some users appeared to be intentionally sourcing supplementation from a variety of fish oil, fish oil concentrates and/or krill oil.
Consumer Confusion — Labels on products were confusing to almost all. Significant variability existed in the daily supplemental dosages of study participants, which ranged from 0 mg per day to more than 10,000.
Dose Response — Serving size/dose doesn’t necessarily match the reality of the dose-response curve, which could have major implications for manufacturers and distributors. At the end of the study, only 19% of participants achieved an omega-3 index of 8% or higher. Forty-four percent had an index level of 4-5.9%, and 8% were below the 4% level. Unlike vitamin D, the variables in how omega-3 is metabolized, vis-à-vis the forms of omega-3 taken, along with the dosage and duration of consumption and the frequency of testing, could all have significant bearing on achieving an omega-3 testing index level of 8%.
Studies move forward
The work continues, with the objective to empower practitioners and their patients with personalized data to monitor and manage their health. We will grow the omega-3 study population to 5,000 people in the next two years. We are launching a parallel study with 500 participants taking either fish oil, krill oil or a combination of the two in an effort to evaluate metabolic response and the impact of dosage on serum levels. Study development is underway for magnesium and vitamin D, and we continue our consumer education campaign on the 15 nutrients people are most deficient in.
All nutrients need large population size databases to test dose response of their products. All practitioners and practice groups, along with their patients, can benefit from being a part of this work. Our association contributions reduce the cost of participation and enable access to savings on the purchase of supplements. We welcome your contribution and participation.
KAREN HOWARD, CEO and executive director of Organic & Natural Health Association, is a visionary and results-focused leader who has spent more than 30 years working with Congress, state legislatures and health care organizations to develop innovative health care policy and programs. She can be contacted at organicandnatural.org.
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