New criteria suggested for accurately reporting bioavailability of nutritional supplements
2010-01-13 BioActives LLC, Worcester, MA.A newly published review of recent CoQ10 and carotenoid research has concluded that “improved bioavailablity” claims are weakened when the statistical analysis of the data shows high inter-subject variance. Inter-subject variance is a critical measurement used in the pharmaceutical industry to assess the absorption differences from patient to patient in order to ensure predictable dosing. The authors present new terms for clarifying these research results by defining reliable and universal bioavailability claims.This review , published in the January 2010 issue of Natural Medicine Journal is entitled “Universal and Reliable Bioavailability Claims: Criteria That May Increase Physician/Consumer Confidence in Nutritional Supplements.”In reviewing CoQ10 and carotenoid bioavailabilty studies, the authors noted that while the absorption difference between subjects was often reported in the statistical analysis, the relevance of these differences to individual consumers was not discussed. Statistically, the higher the difference between subjects, the less likely the claim will apply to an individual. A significant percentage of the studies reviewed reported such high inter-subject variance.

The authors presented a statistical model exploring the effects of high inter-subject variance on bioavailability claims. Using this model, it was possible to make an “improved bioavailability” claim for one formulation over another. Yet, at the same time, it was observed that the claim of greater bioavailability for a formulation with high inter-subject variance will actually only apply to about 50% of the subjects, which translated could mean that the claim will only apply to 50% of consumers.

Dan Kagan Ph.D., a Managing Partner at BioActives LLC, observed “that communicating these issues to physicians and consumer is difficult, as it requires familiarity with descriptive statistics. New standard terms could be helpful for individual consumers to understand whether they would actually benefit from taking the supplement.”

The article proposed two new terms that could improve the validity of bioavailability claims: A reliable claim would apply to roughly 85% population and a universal claim would apply to 99% of the population. Reported this way, physicians would be better able to choose formulations for their patients and consumers would be better able to select products that will likely be effective for them individually.

Parallels were drawn between the new proposed terms and those used in pharmaceuticals. The statistical basis for the terms is also discussed as well as the method for calculating them.

Kagan concludes, “Marketers will be free to judge whether reliable or universal claims are attractive based upon a study’s statistical results. Since products with low inter-subject variance would have a huge advantage over those with high inter-subject variance, product developers would obviously favor formulations that are more likely to benefit more consumers.

Daniel Kagan Ph.D. and Doddabele Madhavi Ph.D. are managing partners at BioActives LLC, the developers of MicroActive® CoQ10 distributed by Maypro Industries. Ginny Bank, MS is the founder and president of Full Spectrum Consulting, Boulder, Colorado. Kenneth Lachlan Ph.D. is Associate Professor of Communications at University of Massachusetts and investigator on the Risk Communication Research Team, National Center for Food Protection and Defense.

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