Supplement Perspectives

Ask These Seven Questions to Get the Best Research

Regular contributor Kathleen Dunn has what you need to know.

Finding dietary ingredients that deliver serious health benefits can feel like a Herculean task at times, even for seasoned product developers. One way I shrink this task down to size is to focus on ingredients backed by randomized controlled trials (RCTs), the gold standard of clinical research. After all, ingredients with this credential are the top contenders for supplements that can make a serious health impact. 

Only some RCTs, however, are robust enough to provide solid evidence to support the “clinically shown” ingredient claims that resonate so well with health-conscious consumers.

These best-in-class RCTs are easy to find when you start by asking seven simple questions:

1. Does the RCT have enough subjects?
When researchers design RCTs, they perform a “power calculation” to determine the minimum number of subjects required to confirm results are statistically significant and clinically relevant. You’ll typically find a statement about it in the Methods section of the study results. For example, “We determined that 100 subjects provide sufficient power to detect a clinically relevant difference at a 95% confidence level (P<.05).” In this example, if at least 100 subjects actually completed the study, it would have statistical power. (Researchers typically start with more subjects than needed for power, knowing some will drop out).

2. Does the RCT use the commercially available ingredient?
A supplier may be actively working on improving an ingredient, creating a better delivery form, concentrating active compounds, or revising processing methods, all in an effort to improve an ingredient’s effectiveness. Thus, an ingredient’s research portfolio may boast “Supported by 10 clinical studies,” but only a few may directly apply to the specific form you are considering for your formula. Like the power calculation, a description of the ingredient is typically found in the Methods section of the study results. If not, ask the supplier or researcher for more details. You can compare this to the ingredient specification to confirm they are similar.

3. Does the RCT use a standalone ingredient?
If you’re exploring the potential benefits of one specific ingredient, you’ll want RCTs that test the effects of just that one ingredient without other active ingredients. A nominal amount of processing aids or other inactive ingredients is fine; you just don’t want other active ingredients in the mix. Why? It would be anyone’s guess as to what ingredient is the real workhorse: your ingredient, another active ingredient, or the blend itself. Of course, if it’s the blend you’re interested in, then focus on RCTs that study the blend rather than its individual ingredients.

4. Does the RCT use a substantially similar dose and daily dosage?
Your final formula should provide an amount per day (the daily dosage) AND an amount per serving (the dose) of the ingredient that is similar to that used in an RCT. Research may show an ingredient has serious benefits when taken as a split dose–twice daily or even three times daily–but data may be lacking to confirm any benefits from the same amount taken once daily. So, you’ll not only want to match the daily dosage, but also the dose.

5. Does the RCT use a similar target group?
An RCT should include subjects that are “substantially similar” to your intended target group. For example, the research subjects should be the same sex, in a similar age range, and have a similar health status. So, an RCT confirming an ingredient promotes weight loss in overweight women would support a similar claim for a product intended for overweight women (but not men).

6. Does the RCT use the same route of administration?
Whether a tablet, capsule, powder, liquid or other form, we swallow supplements, releasing nutrients into the GI tract for absorption. We don’t put them on our bodies, we don’t inject them into our muscles, and we don’t inhale them. Research that delivers an ingredient by any means other than by mouth may be interesting, but has no value when it comes to substantiating claims for dietary supplements.

7. Does the RCT have a direct health outcome measure?
RCTs that include indirect measures of health such as changes in serum biomarkers or relative comparisons of ingredient bioavailability may be interesting, but not terribly impressive. On the other hand, RCTs that include direct measures of health outcomes are top-tier contenders. For example, a calcium supplement clinically shown to reduce fracture risk rather than just show slightly better absorption; a probiotic clinically shown to improve digestive health rather than just increase cell counts in the intestine; an herbal extract clinically shown to improve the range of motion of joints rather than just increase the blood level of its active constituent. You get the idea. RCTs with clinically validated health outcome measures are robust with a capital “R” and deserve serious attention from product developers who want to create products that matter.

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