What Is an Open Label Study and Why It Matters for Product Claims

When brands talk about being clinically tested, the type of study behind that claim matters. One commonly used and often misunderstood research design is the open label study. Especially popular in supplements, skincare, cosmetics, superfoods, and pet health, an open label study offers valuable real-world insights, when designed and communicated correctly.

In this post, we’ll break down what an open label study is, how it works, its benefits and limitations, and why it plays an important role in transparent, credible product marketing.

What Is an Open Label Study?

An open label study is a type of clinical study where both the researchers and the participants know what product is being used. Unlike blinded or placebo-controlled trials, there is no concealment of treatment.

In non-pharmaceutical industries, open label studies are commonly used to evaluate:

• Dietary supplements

• Skincare and cosmetic products

• Functional foods and superfoods

• Pet supplements and topical products

These studies focus on safety, tolerability, user experience, and measurable outcomes under real-world conditions.

How an Open Label Study Works

While simpler than randomized controlled trials, a well-designed open label study still follows a structured methodology:

Key Elements of an Open Label Study

• Defined study objectives (e.g., hydration improvement, joint comfort, skin appearance)

• Specific inclusion and exclusion criteria

• Pre- and post-intervention assessments

• Standardized product usage instructions

• Statistical analysis of collected data

Even without blinding, data collection can include objective measurements such as skin imaging, biometric markers, questionnaires, or veterinary assessments in pet studies.

Why Brands Use Open Label Studies

An open label study offers several advantages, particularly for emerging brands or those seeking cost-effective clinical substantiation.

1. Real-World Relevance

Participants know what they are using, which closely mirrors actual consumer behavior. This makes findings highly relatable for marketing and education.

2. Faster and More Affordable

Compared to double-blind or placebo-controlled trials, an open label study is:

• Quicker to launch

• Less complex to manage

• More budget-friendly

This makes it accessible for small and mid-sized brands seeking clinical credibility.

3. Supports Transparent Marketing

When clearly disclosed as an open label study, results help brands demonstrate honesty and compliance with FTC expectations around advertising claims.

Open Label Study vs. Blinded Studies

It’s important to understand where an open label study fits in the hierarchy of evidence.

Feature	Open Label Study	Blinded Study
Participant awareness	Yes	No
Placebo control	Usually no	Often yes
Cost	Lower	Higher
Real-world conditions	High	Moderate
Bias control	Limited	Strong

An open label study may not eliminate expectancy bias, but it still provides valuable preliminary or supportive clinical evidence, especially when claims are carefully worded.

Can You Make Claims from an Open Label Study?

Yes, but how you make claims matters.

Appropriate claims supported by an open label study include:

• “Clinically tested in an open label study”

• “Participants reported improvements in…”

• “Observed results after X weeks of use”

Claims should never imply placebo control or blinding if those elements were not part of the study. Transparency is key to remaining compliant with FTC advertising guidelines.

Best Practices for Using Open Label Study Results

To maximize credibility and consumer trust, brands should:

• Clearly state the study type as an open label study

• Disclose sample size and duration

• Avoid overstated or causal language

• Combine with other evidence when possible (mechanistic data, ingredient research)

When done correctly, an open label study can be a powerful tool in a broader clinical validation strategy.

Is an Open Label Study Right for Your Brand?

An open label study is not a shortcut, it’s a strategic choice. For supplements, cosmetics, skincare, and pet health products, it offers an affordable, ethical, and transparent way to evaluate performance and support responsible marketing claims.

When paired with sound methodology and honest communication, open label studies help brands stand out in crowded markets while building long-term consumer trust.

Interested in running an open label study for your product? Citruslabs designs affordable, transparent clinical studies to help brands support credible, compliant marketing claims. Get in touch with us today to learn more!