In our previous article, The Vegan Problem: Which Vegan Fashion Certifications Can You Actually Trust?, we explored how independent certifications can help verify vegan claims while highlighting why certification alone cannot determine a product’s overall sustainability or ethical impact. The same distinction is important when evaluating materials widely perceived as natural or sustainable. From wool and silk to cotton and cashmere, natural origin of a fiber is often automatically associated with sustainability —but these assumptions can overlook the environmental impacts, animal-welfare concerns, and supply-chain challenges behind the fibres we wear.
As the fashion industry increasingly questions its dependence on synthetic materials, the conversation risks replacing one oversimplification with another. Moving away from fossil-based fibres is important, but choosing a natural fiber does not automatically make a garment more sustainable, responsibly produced, or cruelty-free. To understand the real impact of a material, we need to look beyond its origin.
The Rise of the ‘Natural Is Better’ Narrative
The backlash against polyester has become increasingly visible in fashion. Consumers, designers, and commentators are questioning the widespread use of synthetic fibres, particularly in clothing marketed as premium or sustainable. This conversation reflects legitimate concerns: conventional polyester is predominantly fossil-based, and synthetic textiles can contribute to microplastic pollution and create challenges at the end of their life cycle. However, the debate can sometimes imply that replacing synthetics with natural fibres is a straightforward solution.
The scale of the industry helps explain why this is a complicated issue. According to Textile Exchange’s Materials Market Report 2026, global fibre production reached an estimated 139 million tonnes in 2025. Polyester accounted for 59% of that total, and 88% of polyester production was fossil-based. Animal fibres, meanwhile, represented approximately 1% of global fibre production combined.
These figures illustrate the fashion industry’s reliance on synthetic materials, but they do not establish that natural fibres are inherently better. Different materials have different environmental profiles, and those profiles depend on factors such as how a fibre is produced, processed, transported, used, and ultimately disposed of.
The problem is not that fashion is questioning polyester. It is that the conversation can become a binary choice between ‘bad’ synthetics and ‘good’ natural fibres. As Kyle MacNeill discusses in Fashion’s Complicated Poly Relationship for Vogue, the fashion industry’s relationship with polyester is more complicated than a simple rejection of the fibre suggests.
Such a distinction leaves little room for the complexity of material production—and can obscure the impacts of materials that have benefited from a positive reputation for generations.
‘Natural’ Does Not Automatically Mean Sustainable
Natural fibres are often described as renewable, biodegradable, or environmentally friendly. Although these characteristics can be relevant, none provides a complete picture of a material’s sustainability.
A 2023 review, Wool and Silk Fibres from Sustainable Standpoint, highlights how natural and renewable origins are frequently associated with sustainability, even though a comprehensive assessment requires more than those characteristics alone. Life cycle assessment (LCA) is one important method for examining environmental impacts across different stages of a product’s life.
Depending on the material, these stages can include agricultural production, resource use (such as land and water), processing, dyeing, manufacturing, transport, consumer care, and disposal. The impact of each stage varies. A fibre that performs well in one environmental category may have greater impacts in another.
Cotton is a textbook example. It is a widely used natural fibre, but its production can require substantial water, energy, fertilisers, and pesticides. The environmental consequences vary according to the growing region, agricultural practices, processing methods, and conditions in the surrounding ecosystem.
A 2025 systematic literature review, Environmental Sustainability of Cotton: A Systematic Literature Review of Life Cycle Assessments, examined the environmental performance of cotton across different production systems. Its findings illustrate that organic cotton does not necessarily have lower impacts in every category or under every measurement method. Organic production can reduce certain impacts per unit of cultivated land, while lower yields can result in higher impacts per unit of cotton produced in some comparisons.
This does not mean organic cotton is a poor choice. It means that the label ‘organic’ cannot answer every question about a material’s environmental performance. Production methods matter, but so do location, yield, resource availability, processing, and the way the final product is used.
The same principle applies to natural materials more broadly: a material’s origin is only one part of its environmental impact, and ‘natural’ does not automatically mean lower-impact than synthetic. In fact, it might be the opposite. The Higg Material Sustainability Index (MSI), developed by Cascale (formerly the Sustainable Apparel Coalition), assesses fibres across five indicators: global warming potential, water scarcity, eutrophication, fossil fuel depletion and chemistry. Within this framework, synthetic fibres such as polyester and nylon can score better than conventional cotton, while animal-derived fibres such as wool, alpaca and silk can receive significantly higher impact scores.
Yet the MSI only measures impacts from raw material extraction to the factory gate, excluding the use and end-of-life phases, and has faced criticism over data transparency, generalised production averages and the risk of oversimplifying complex environmental trade-offs. As controversial as this index is, it does highlight one important point: natural and animal-derived fibres do come at a significant cost in terms of resource use and greenhouse gas emissions.
Cashmere: The Environmental Cost Behind Luxury
Cashmere is often associated with softness, quality, longevity, and luxury. Yet the fibre’s environmental challenges demonstrate why a premium image should not be confused with responsible production.
Much of the world’s cashmere comes from goats raised in regions including Mongolia and China. Growing demand for the fibre has contributed to concerns about herd sizes and pressure on fragile grassland ecosystems. In Mongolia, overgrazing and climate change have been identified as significant drivers of grassland degradation, affecting biodiversity, soil conditions, and the livelihoods of communities dependent on pastoralism. Emily Chan explores these tensions in Can Cashmere Ever Be Sustainable? for British Vogue.
The issue is not that goats produce cashmere. It is how many animals are raised, where they graze, how herds are managed, and whether rangelands have sufficient time and capacity to recover. Responsible land management and support for herders are therefore essential parts of any meaningful response.
Environmental impacts also extend beyond grazing. A 2026 study, Estimating Carbon Footprints and Economic Trade-Offs in Mongolia’s Cashmere Value Chain: An Integrated System Dynamics Approach, modelled emissions across a Mongolian cashmere value chain. In that specific model, electricity used during fibre dehairing accounted for 46.79% of greenhouse gas emissions, while transporting dehaired cashmere to end processors accounted for a further 33.5%.
These figures relate to the particular value chain studied, rather than all cashmere production, but they demonstrate how processing and transport can contribute significantly to a material’s environmental footprint.
Certification can help improve practices, but it also needs scrutiny. In January 2026, the Sustainable Fibre Alliance (SFA) published a public position statement acknowledging weaknesses in the implementation of elements of its certification system during 2022–2024. In some cases, environmental requirements had not been fully audited for all Mongolian herding organisations supplying cashmere sold as SFA Certified.
An independent investigation found no evidence of wrongdoing, fraud, deliberate misrepresentation, or negative sustainability outcomes resulting from these gaps. The organisation outlined corrective actions and a programme to strengthen its systems.
This example does not mean that all certified cashmere is unreliable. Rather, it illustrates why consumers and brands should examine what a standard covers, how compliance is assessed, and how shortcomings are addressed.
Cashmere can provide income and support traditional livelihoods, so the issue cannot be reduced to a simple judgement about herders or individual producers. Nevertheless, a material’s luxurious feel, natural origin, and high price are not evidence that its production is environmentally responsible.
Wool: Natural Fibre, Animal-Welfare Questions
Similarly to cashmere, wool is renewable in the sense that sheep grow a new fleece, and the fibre can be durable and useful across a range of garments. However, its production raises questions that cannot be answered by environmental assessments alone.
Animal welfare varies with farming practices, handling, transport, and the conditions in which sheep are kept. One particularly contested practice is mulesing, in which strips of skin are removed from around a sheep’s breech to reduce the risk of flystrike. The practice raises significant animal-welfare concerns.
Standards such as the Responsible Wool Standard (RWS) aim to address some of these issues. The RWS includes animal-welfare requirements, land management, social criteria, third-party auditing, and chain-of-custody requirements. Its criteria include non-mulesing. Such standards can offer brands a framework for improving and verifying particular aspects of production.
However, their reach remains limited. Textile Exchange reported that RWS-certified greasy wool accounted for approximately 4.5% of global greasy wool production in 2025 in its Materials Market Report 2026. This means that the overwhelming majority of global greasy wool production was outside this particular standard that year. It does not mean that all uncertified wool comes from poor practices, but it does show that certification coverage remains far from universal.
There is also a fundamental ethical distinction. A standard may improve animal welfare and land management, but for consumers who reject the use of animals as sources of clothing, better farming practices do not resolve the underlying objection to using animal-derived fibres.
This distinction matters because environmental responsibility and animal ethics are related but separate questions. A material may perform comparatively well in some environmental assessments while remaining unacceptable to people who consider the use of animals in fashion inherently unethical.
Silk: When Biodegradability Does Not Resolve Animal Ethics
Silk is another material frequently associated with natural luxury. It is a natural protein fibre, valued for its drape, softness, and distinctive appearance. Depending on the conditions in which it is discarded, silk can also biodegrade. Yet these characteristics do not tell the whole story of its production.
Conventional silk production typically involves killing silkworm pupae inside their cocoons before the moths emerge. This preserves the continuous filament needed to produce conventional silk yarn, as discussed in Sustainable Silk Production by T. Karthik and R. Rathinamoorthy.
The practice raises an ethical issue that cannot be resolved simply by describing the resulting fabric as natural or biodegradable.
Different silk-production methods may have different implications for animal welfare and fibre quality, so individual claims need to be examined rather than treated as interchangeable. Nevertheless, the central point remains: biodegradability describes a material’s potential behaviour at the end of its life; it does not establish that the process used to produce it was cruelty-free.
For vegan fashion, this distinction is particularly important. A material can have desirable environmental characteristics and still conflict with vegan principles. Sustainability claims should not be used to obscure the ethical questions involved in obtaining animal-derived fibres.
The Problem Extends Beyond Animal Fibres
Although wool, cashmere, and silk raise specific animal-welfare questions, the wider problem is not limited to animal-derived materials. Plant-based fibres and materials can also carry environmental and social costs.
Cotton cultivation can contribute to water depletion in vulnerable regions, while fertiliser and pesticide use can affect ecosystems and human health. Manufacturing processes, including dyeing and finishing, may require substantial energy and water and generate wastewater. These impacts are not identical across all cotton products, and better agricultural and manufacturing practices can make a meaningful difference, as the 2025 systematic review of cotton life cycle assessments demonstrates.
Similarly, describing a material as plant-based does not automatically establish that it is low-impact. The relevant questions include which plant or feedstock is used, how it is cultivated, what processing is required, which chemicals are involved, and how much of the finished material actually comes from that source.
The same caution applies to vegan alternatives. A material that avoids animal-derived inputs may still rely on fossil-based polymers, resource-intensive production, or processing methods with environmental drawbacks. Vegan status alone does not establish sustainability, just as natural origin alone does not establish ethical production.
This is not an argument against natural fibres or vegan alternatives. It is an argument for evaluating them using consistent criteria rather than assuming that a particular material category is automatically preferable.
When Marketing Claims Replace Evidence
The fashion industry’s use of broad environmental language makes these distinctions harder for consumers to navigate. Words such as ‘natural’, ‘responsible’, ‘eco-friendly’, ‘conscious’, and ‘sustainable’ can suggest a level of environmental or ethical performance that has not necessarily been demonstrated.
The European Commission has highlighted the scale of the problem. Its Green Claims information reports that 53% of environmental claims provide vague, misleading, or unfounded information, while 40% lack supporting evidence. It also reports that half of green labels offer weak or non-existent verification. These figures concern environmental claims and labels across product categories generally, rather than natural fashion alone.
Material composition is another challenge. In June 2026, an EU testing campaign examined 132 clothing items and found that 49—37% of the sample—had labels that did not accurately reflect the materials used. The European Commission’s report on inaccurate clothing labels identified issues including incorrect fibre percentages, the presence of different fibres from those declared, and incorrectly named fibres.
These results do not establish that every inaccurate label was deliberately misleading. They do, however, demonstrate that consumers cannot always rely on a product description without question. When natural fibres are perceived as inherently preferable, inaccurate composition claims can also undermine consumers’ ability to make informed decisions.
The solution is not to dismiss every sustainability claim. It is to demand greater specificity and evidence. If a brand describes a material as responsible, it should explain what that means: which environmental or social criteria are covered, what evidence supports the claim, and whether the information has been independently verified.
A claim about animal welfare should not be treated as proof of low environmental impact. A claim about recycled content should not automatically imply ethical production. And a claim about natural origin should not be allowed to stand in for evidence about the entire supply chain.
Beyond the Natural-versus-Synthetic Debate
A more credible approach to material choice begins by moving beyond the assumption that fibres can be divided neatly into sustainable and unsustainable categories based on their origin alone.
For brands, this means assessing materials according to their intended use, durability, production methods, environmental impacts, supply-chain transparency, and end-of-life options. It also means distinguishing between environmental performance and animal ethics, rather than presenting improvements in one area as proof of responsibility in every other area.
For consumers, a more useful set of questions might include:
- What is the material actually made of? Check the fibre composition and the proportion of each component, rather than relying on broad descriptions such as ‘natural’ or ‘plant-based’.
- How was it produced? Consider agricultural practices, animal-welfare conditions where relevant, chemical use, water consumption, and processing.
- What does the certification verify? Look at the standard’s scope, traceability requirements, auditing process, and limitations.
- Will the garment last? Durability, repairability, and realistic care requirements influence how useful a product remains over time.
- What happens at the end of its life? Fibre blends, finishes, trims, and local recycling or disposal infrastructure can affect whether a garment can be reused or recycled effectively.
No single answer will resolve every trade-off. A fair comparison requires considering the purpose of the product, the quality of the available evidence, and the impacts that matter most—without allowing marketing language to replace that assessment.
Natural Is Not a Synonym for Ethical
Natural fibres have important roles in fashion, just as innovative vegan alternatives can help reduce reliance on animal-derived materials. Neither category, however, should be treated as automatically sustainable or ethical.
Cashmere demonstrates how demand for a luxury fibre can put pressure on fragile ecosystems. Wool shows that renewable production does not eliminate animal-welfare concerns. Silk illustrates how biodegradability does not resolve the ethics of conventional production. Cotton reminds us that plant origin does not remove the need to consider water, chemicals, land, and processing.
The answer is not to replace the belief that ‘natural is better’ with the opposite assumption that all natural materials are bad. It is to reject shortcuts that make complex supply chains appear simple.
For vegan fashion in particular, this means evaluating materials through two complementary lenses: whether they avoid animal-derived inputs, and what their broader environmental and social impacts are. A material can meet one criterion without meeting the other.
Ultimately, responsible fashion requires more than choosing a fibre with a reassuring name. It requires transparent claims, credible evidence, meaningful standards, and a willingness to examine the consequences of production rather than relying on the associations attached to a material.
Natural does not automatically mean sustainable. Renewable does not automatically mean ethical. And a convincing claim is not the same as a verified one.
Sources and Further Reading
- Vegan Fashion Repository, The Vegan Problem: Which Vegan Fashion Certifications Can You Actually Trust?, 24 August 2026.
- Textile Exchange, Materials Market Report 2026, 22 September 2026.
- Kyle MacNeill, Fashion’s Complicated Poly Relationship, Vogue, 7 May 2026.
- Wool and Silk Fibres from Sustainable Standpoint, Sustainable Fibres for Fashion and Textile Manufacturing, 2023.
- Giuseppe Salvatore Vitale et al., Environmental Sustainability of Cotton: A Systematic Literature Review of Life Cycle Assessments, Journal of Agriculture and Food Research, vol. 22, 2025, article 102069.
- Emily Chan, Can Cashmere Ever Be Sustainable?, British Vogue, 15 January 2025.
- Joshua Aboah et al., Estimating Carbon Footprints and Economic Trade-Offs in Mongolia’s Cashmere Value Chain: An Integrated System Dynamics Approach, Agricultural Systems, vol. 237, 2026, article 104824.
- Sustainable Fibre Alliance, SFA Public Position Statement | January 2026, 15 January 2026.
- Textile Exchange, Responsible Wool Standard (RWS).
- Sustainable Silk Production, Sustainable Fibres and Textiles, 2017.
- European Commission, Green Claims.
- European Commission, Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs, Inaccurate Clothing Labels a Systemic Issue, EU Testing Finds, 18 June 2026.
Author
Discover more from Vegan Fashion Repository
Subscribe to get the latest posts sent to your email.