Mastering Natural Ingredient Claims with ISO 16128

Why “Natural” Needs Definition

In today’s luxury skincare market, “natural” is one of the most powerful words a brand can use. Not only does it evoke a sense of purity and sustainability, but it also fosters consumer trust and gives the impression of a brand’s ethical commitment. However, the reality beneath this appealing image is far more nuanced: the term “natural” within cosmetics lacks a universally accepted definition. Unlike the food or agricultural sectors, which have well-established, regulated organic and natural standards, cosmetics in both the EU and UK operate without such legal clarity. This absence of regulation often results in widespread confusion, inconsistent product claims, and, at times, accusations of greenwashing as companies interpret “natural” to suit their own marketing narratives.

To address this ambiguity, ISO 16128 was developed, a globally recognised standard aimed at bringing more clarity, structure, and scientific rigor to claims about natural ingredients in cosmetics. Released in two parts (2016 and 2017), ISO 16128 provides a robust framework that guides brands in classifying ingredients and in accurately calculating natural origin indices. For professionals like formulators, CEOs, and R&D leads, the standard acts as a crucial navigational tool; it enables robust claim substantiation anchored in scientific methodology rather than subjective opinion or marketing spin.

The Role of ISO 16128 in Luxury Skincare

Credibility lies at the heart of luxury brands. Discerning consumers expect more than just rich textures and elevated sensory experiences, they also demand full transparency and reliable proof behind product claims. ISO 16128 offers a bridge between brand storytelling and science by:

• Clearly defining ingredient categories, such as natural, derived natural, organic, derived organic, and synthetic.
• Introducing methods for calculating the percentage of natural-origin content, both at the ingredient level and across the completed product.
• Establishing a platform for alignment with highly regarded third-party certifications like COSMOS and NATRUE.

By implementing ISO 16128, brands can provide accurate and transparent percentages to support their “natural” claims, meeting the expectations of not only regulators and certifiers but also well-informed consumers who are increasingly wary of vague or misleading messaging.

ISO 16128‑1: Definitions and Ingredient Categories

The first section of the standard is devoted to clear definitions. It categorizes cosmetic ingredients according to both their original source and the nature of processing involved:

• Natural Ingredients: Extracted directly from plants, animals, or minerals through non-chemical means, such as cold-pressing or distillation.
• Derived Natural Ingredients: These originate from natural sources but undergo a degree of modification, with at least 50% of the molecular structure coming from nature. For example, a mild esterification of coconut oil resulting in a coconut-derived surfactant.
• Organic Ingredients: Natural ingredients cultivated and harvested in accordance with recognized organic farming standards.
• Derived Organic Ingredients: Modified ingredients for which the majority of their structure is retained from certified organic sources.
• Synthetic Ingredients: Substances derived from fossil fuels or those that have been chemically altered in such a way that they no longer meet the criteria for being 'natural.'

This systematic classification is vital in reducing the risk of deceptive marketing. Importantly, any material sourced from fossil fuels is categorically excluded from being described as “natural,” which protects both brand integrity and consumer interest.

ISO 16128‑2: Calculating Indices

The second part of the standard outlines the specific formulas to be used for calculating the natural origin indices of cosmetic products. These calculations empower brands to make claims such as “95% natural origin” with confidence and consistency.

Key steps include:

• Ingredient Audit: Carefully review each raw material’s source and classification.
• Mass Balance Calculation: Assign accurate weight percentages to all components included in the formulation.
• Application of Formulas: Utilize the ISO 16128‑2 equations to determine the product’s overall natural origin index.

Such a process not only ensures a uniform approach across the industry but also supplies the necessary documentation for certification bodies like COSMOS or NATRUE, which routinely require validated natural origin data as part of their approval process.

What ISO 16128 Does Not Cover

Despite its strengths, ISO 16128 is not intended as a catch-all. Some critical aspects remain outside its remit, including:

• Product Safety: Evaluations of toxicity and safety still fall under the scope of Cosmetic Product Safety Reports (CPSRs).
• Environmental Impact: Lifecycle analysis and broader sustainability assessments are not addressed by ISO 16128.
• Marketing Narratives: The standard provides numbers, not storytelling; building meaningful claims requires additional context.

This is why brands must turn to guidance such as the Common Criteria, which emphasizes that claims should be transparent, evidence-based, and must not mislead consumers into thinking “natural” equates to increased safety. The UK’s Advertising Standards Authority (ASA) underscores this: “Claims that organic products are inherently safer than non‑organic ones are likely to be problematic.”

Why CEOs and R&D Leads Should Care

For CEOs, adherence to ISO 16128 is a strategic move to protect and enhance brand reputation in an era where consumer skepticism and regulatory scrutiny are at an all-time high. Unsubstantiated or vague “natural” claims can jeopardize trust and open brands to reputational and legal risks. Conversely, substantiated percentages and clear compliance offer a compelling narrative to justify premium positioning and build long-lasting trust.

For R&D leads, the standard is a practical blueprint for responsible and innovative formulation. It not only facilitates the creation of products that meet evolving consumer preferences and regulatory standards but also enables seamless collaboration across teams—whether working with suppliers, certification agencies, or marketing departments.

Tip for Formulators

While ISO 16128 is not a tool for crafting compelling marketing slogans, it does provide the scientific backing needed for credible product stories. Formulators should leverage it to develop claims that are precise and compliant with local regulations and documentation needs, such as CPSRs or Product Information Files. Consider the following best practices:

• Replace broad phrases like “100% natural” with substantiated statements, such as “Formulated with 98% natural origin ingredients, calculated per ISO 16128 methodology.”
• Rather than implying inherent safety, highlight your transparency: “Our natural origin index is verified through ISO 16128 calculations, providing clear and reliable information.”

This responsible approach helps prevent consumer confusion while reinforcing brand integrity and trust.

Predictions: The Future of “Natural” Claims

Looking to the future, several key trends are set to influence how ISO 16128 will be applied in the industry:

• Digital Transparency: The use of QR codes and digital platforms to link consumers directly to ingredient substantiation and audit trails.
• Third‑Party Validation: Independent certifications will become increasingly standard, particularly in the luxury skincare segment.
• Global Harmonisation: ISO 16128 is well-positioned to serve as a universal baseline as regulations and standards converge across regions.
• *Sustainability Metrics: There will be a growing integration of environmental impact measurements alongside natural origin indices to further enhance a product’s sustainability credentials.

Forward-looking brands that embrace these developments will meet, and often exceed, regulatory and consumer expectations for openness and authenticity.

Conclusion: From Compliance to Competitive Advantage

In today’s luxury skincare landscape, effectively mastering natural ingredient claims is not just a compliance exercise—it’s an essential pillar of leadership and competitive differentiation. ISO 16128 delivers the scientific groundwork needed to substantiate claims, align with esteemed certifications, and foster robust consumer trust.

For CEOs, it safeguards and props up brand equity. For R&D professionals, it guides responsible innovation. For formulators, it brings much-needed clarity to a complex and evolving marketplace. And for consumers, it transforms “natural” from a mere marketing buzzword into a substantiated and meaningful promise.

At Olalla Consulting, we view substantiation as a path to leadership. By fully embracing ISO 16128, brands don’t just tick regulatory boxes, they elevate their stories, reinforce trust, and secure a place at the forefront of luxury skincare innovation.