After considering claims made by i-Health Inc. for its Culturelle probiotic supplements, the National Advertising Division (NAD) recommended that the company discontinue television and online advertising as well as product packaging.

Competitor Procter & Gamble Co. challenged statements featuring similar iterations of the core claim that Culturelle is the “most clinically proven effective” or “#1 proven effective” probiotic. For example, i-Health promoted Culturelle with the statement that its ingredient “LGG is the most proven effective strain* … (*Based on the studies of a range of benefits throughout the lifespan”).” Proximate to the claim, i-Health also stated that LGG is “the only one you need to help support good digestion and immune health.”

P&G argued that the claims communicated a message that i-Health’s use of Lactobacillus rhamnosus GG (LGG) provides the most effective probiotic in terms of overall health-related benefits but that i-Health failed to support the comparative superiority claims. P&G also took issue with the advertiser’s disclaimers, alleging they were insufficient to qualify the “most proven effective” claim because the number of studies named in the disclaimers demonstrate only that LGG is the most studied probiotic, not the most effective.

In response, i-Health explained that it used publicly available records on to identify published clinical trials on the three most frequently studied strains of probiotics (including LGG) and that it reviewed the studies for features such as regimen description, outcomes measured and cohorts studied and then aggregated the results. In a series of charts provided to the NAD, the advertiser argued that the results demonstrated that LGG had the highest number of “positive outcomes” for any strain and that no other probiotic strain has returned as many positive or successful clinical studies as LGG nor been proven effective across such a wide range of age categories and for such a wide variety of health benefits.

But the NAD “had significant concerns with this approach.” While PubMed “may be one of the largest public repositories for clinical studies, it is not necessarily an exhaustive source of clinical studies,” the self-regulatory body wrote. “By solely focusing on publicly available studies from a single source, the advertiser failed to account for studies that may have been published elsewhere, as well as unpublished or proprietary testing that may be entirely relevant but not publicly available. Further, the advertiser acknowledged that the aforementioned studies were independently conducted and, therefore, had differences as to clinical protocols, such as dosage, formulation, and study population.”

The NAD was also unclear whether the “positive” results were consistently defined by the various study authors, and without critical information such as dosage, formulation and study population, “NAD had no way to evaluate whether the studies reviewed by the advertiser were a good fit for the advertiser’s claim.”

“Additionally, tallying of the number of successful studies on an ingredient does not provide information about the quality of the results or the study itself,” according to the decision. “For example, a study may report a so-called ‘positive’ result that was not statistically significant or consumer meaningful, and consequently, unreliable.”

“Thus, even if NAD accepted that the advertiser’s interpretation was the only reasonable interpretation, the support provided would have been inadequate,” the self-regulatory body said. “However, NAD was not convinced by the advertiser’s argument that the claims at issue were not comparative in nature.”

Simply because a claim fails to specify an object of comparison does not necessarily mean it is not making a comparison, the NAD cautioned, and the use of “#1” suggests that Culturelle is ranked first or is a leader in a quantifiable way and is inherently comparative.

“Strong health benefit claims require equally strong competent and reliable scientific evidence in the form of human clinical trials that are methodologically sound and statistically significant to the 95% confidence level, with results that translate into meaningful benefits for consumers that relate directly to the performance attributes promised by advertising,” the NAD wrote. “The use of the terms ‘most clinically proven effective’ and ‘#1 clinically proven effective’ indicate to consumers that there is scientific evidence that proves or ‘establishes’ the truth of the advertiser’s claim.”

Without the necessary studies to support the claims, the NAD recommended that i-Health discontinue its “LGG is the most proven effective,” “LGG is the most clinically proven effective strain” and “Exclusively with the #1 Proven Effective Probiotic” claims.

To read the NAD’s press release about the decision, click here.

Why it matters: Rejecting the advertiser’s argument that its claims were not comparative, the NAD noted that failing to identify the object of comparison did not mean a claim was not comparative. “[T]he fact that the claims use comparative language but do not make clear the basis of the comparison leaves them open to interpretation,” and multiple reasonable interpretations, the NAD wrote.