The “Unflavored” Movement: Who Vapes Base-Only and Why?

Author: R&D Team, CUIGUAI Flavoring

Published by: Guangdong Unique Flavor Co., Ltd.

Last Updated: Jul 01, 2026

WhatsApp & Telegram: +86 189 2926 7983

Unflavored E-Liquid Base

Introduction: A Quiet Revolution in the Vape Aisle

Walk into any specialty vape shop and you will find shelves lined with hundreds of flavors — ice mango, strawberry cheesecake, blueberry lychee, tobacco royale. But a growing, understated segment of vapers has opted to strip the experience down to its absolute minimum: propylene glycol (PG), vegetable glycerin (VG), and, optionally, nicotine. No color. No sweeteners. No added scent. Nothing but the base.

This phenomenon — often called “base-only” or “unflavored” vaping — is not merely a niche curiosity. It is a deliberate consumer choice driven by a convergence of health considerations, regulatory dynamics, DIY culture, and sensory preference. For manufacturers, flavor formulators, and B2B buyers in the e-liquid supply chain, understanding this movement offers critical insight into market segmentation, regulatory risk, and product innovation strategy.

In this article, we conduct a comprehensive technical and behavioral analysis of unflavored vaping: who does it, why they do it, what the science says about their base liquid, and what it means for the future of the e-liquid flavor industry. We draw on peer-reviewed research, regulatory documentation, and industry market data to build a complete picture of this emerging niche that is quietly reshaping how e-liquid products are conceptualized and marketed.

1. Defining “Unflavored” in the Context of E-Liquids

1.1 What Is an Unflavored E-Liquid?

An “unflavored” e-liquid — also referred to as a base liquid, blank base, or unflavored base — is an e-liquid formulation that contains no intentionally added flavor compounds. It typically consists of:

• Propylene Glycol (PG): A colorless, odorless synthetic liquid with USP-grade purity, acting as a solvent and carrier for nicotine and other active components. PG contributes to “throat hit.”
• Vegetable Glycerin (VG): A naturally derived, viscous liquid from plant oils. VG contributes to cloud density and provides a faint, inherent sweetness with no added flavoring.
• Nicotine (optional): Present as freebase nicotine or nicotine salt at concentrations from 0 mg/mL to 50+ mg/mL, depending on the consumer’s preference and the device type.
• Distilled Water (optional): Sometimes added in small percentages (1–5%) to reduce viscosity, particularly in high-VG formulations.

No aroma compounds, flavor extracts, essential oils, sweeteners, or colorants are included. In the absence of flavor molecules, the baseline sensory experience comes entirely from the thermal and mechanical interaction of PG and VG molecules with the vapor stream.

1.2 The Regulatory Gray Zone: Is Unflavored Really “Flavorless”?

This is a technically and legally nuanced question. In 2021, the U.S. Food and Drug Administration (FDA) clarified in its enforcement guidance that unflavored e-liquids — particularly “base liquids designed to have flavors added to them” — are still classified as “flavored” products under the Tobacco Control Act if they are intended for flavoring purposes. This ruling reflects a functional definition: any product whose primary purpose is to serve as a flavor vehicle may be subject to the same PMTA (Premarket Tobacco Product Application) requirements as conventional flavored e-liquids.

However, for end-consumer products sold as “plain base” for personal vaping — not as DIY additives — the regulatory treatment varies significantly by jurisdiction. Understanding these nuances is essential for manufacturers and brand owners operating across multiple markets.

2. Market Context: How Big Is the Unflavored Segment?

The global e-liquid market was valued at approximately USD 5.25 billion in 2026 and is forecast to reach USD 6.89 billion by 2031, growing at a CAGR of 7.69%, according to Mordor Intelligence (2026). Within this market, flavored e-liquids dominate — accounting for 95.48% of total revenue in 2025. Yet the unflavored segment, while small, is advancing at a notably faster growth rate of 9.35% CAGR through 2031, outpacing several established flavor categories.

This asymmetric growth signals a structural shift. Several factors are simultaneously pushing consumers toward unflavored options:

• Stricter flavor regulations in key markets (California, EU member states, parts of Asia)
• A rising DIY culture where consumers mix their own concentrates onto neutral bases
• Health-conscious vapers seeking to minimize chemical exposure from flavoring agents
• Experienced vapers experiencing “flavor fatigue” who prefer the clean taste of pure base
• Corporate and institutional procurement of base for private-label or OEM e-liquid production

For flavor concentrate manufacturers like CUIGUAI Flavoring, this shift is instructive: the growing unflavored base segment represents not competition, but a companion market — and understanding it is key to serving both ends of the value chain.

PG VG Nicotine Diagram

3. The Technical Chemistry of Vaping a Base-Only Liquid

3.1 Sensory Properties of PG and VG

To understand why anyone would vape an unflavored base, it is essential to appreciate the inherent sensory characteristics of PG and VG themselves. These compounds are not chemically inert — they have distinct physical and sensory properties:

According to a study published in Aerosol Science and Technology (Taylor & Francis, 2020), increasing the PG/VG ratio in nicotine-free e-liquids resulted in measurable differences in particle loss rate and aerosol density. This has direct practical implications for the unflavored vaper: the PG/VG ratio becomes the primary lever for customizing the vaping experience in the complete absence of flavor.

3.2 The Role of Nicotine in Sensory Experience

For base-only vapers who include nicotine, the compound itself contributes meaningfully to sensory perception. Freebase nicotine at concentrations above 6 mg/mL introduces a characteristic peppery, alkaline “bite” at the back of the throat — a sensation many experienced vapers associate with authenticity and satisfaction. Nicotine salt formulations (protonated nicotine), by contrast, deliver significantly higher nicotine concentrations with markedly reduced harshness, making them suitable for mouth-to-lung (MTL) devices.

This pharmacological dimension is not trivial. Research from the National Institutes of Health (NIH) indicates that the form of nicotine — freebase versus salt — significantly influences the user’s puffing behavior, absorption rate, and satisfaction response. For unflavored vapers seeking pure nicotine delivery without flavor masking, understanding nicotine chemistry is essential.

3.3 Thermal Behavior of Base Liquids Under Vaporization

When a PG/VG base is heated to vaporization temperatures (typically 180–260°C in standard sub-ohm devices), several chemical processes occur:

• PG undergoes slight thermal decomposition above 200°C, producing trace quantities of propylene oxide, acrolein, and acetaldehyde — all of which are regulated by public health authorities.
• VG decomposes at higher temperatures, yielding acrolein as the primary decomposition product — a known airway irritant linked to respiratory inflammation.
• In the absence of flavoring compounds, there are no additional reactive species introduced, which theoretically reduces the cumulative toxicant load in the aerosol.

This is a key argument made by proponents of unflavored vaping: fewer input chemicals means fewer opportunity for hazardous thermal degradation products. However, it is critical to note that PG and VG are not without risk themselves, and the apparent “purity” of a base liquid does not render it harmless — a nuance that responsible manufacturers must communicate clearly.

4. Who Vapes Unflavored? A Behavioral Taxonomy

Understanding the unflavored vaping community requires moving beyond demographics and into behavioral psychology and use-case analysis. Based on community research, user surveys, and platform analytics, we can identify at least six distinct consumer archetypes:

4.1 The Health-Conscious Minimalist

This archetype prioritizes harm reduction above all else. They have typically done considerable research into e-liquid chemistry and concluded that the fewer additives in their base, the safer their experience. They are often converted smokers who view vaping purely as a cessation or substitution tool, not a recreational activity.

For the health-conscious minimalist, flavor additives represent an unnecessary variable — an additional set of chemical compounds whose inhalation safety, under real-world vaporization conditions, remains incompletely understood. This position is scientifically defensible: as documented by the U.S. Centers for Disease Control and Prevention (CDC) in its 2019 EVALI (E-cigarette or Vaping Product Use–Associated Lung Injury) investigation, certain flavoring additives — particularly vitamin E acetate — can pose serious inhalation hazards even when derived from otherwise benign sources. For a more detailed analysis of unsafe flavoring ingredients, see our technical reference: Flavor Ingredients to Avoid in E-Liquids: A Practical Guide.

4.2 The DIY Mixer

Perhaps the most commercially significant archetype, the DIY mixer purchases unflavored base as a blank canvas for custom formulation. Armed with flavor concentrates purchased separately — often in bulk from specialist suppliers — they create unique e-liquid profiles calibrated to their exact taste preferences.

This consumer group is highly knowledgeable, often possessing detailed understanding of flavor concentrate usage rates, PG/VG solubility, steeping processes, and nicotine calculation. They are, in effect, micro-scale flavor formulators. The DIY mixer community has its own extensive online knowledge base, covering everything from using mixing calculators to sourcing pharmaceutical-grade ingredients.

For flavor concentrate manufacturers, the DIY segment is a high-value B2B-adjacent market. Providing high-quality, food-grade, vape-compatible flavor concentrates — precisely the product line offered by CUIGUAI Flavoring across our Electronic Cigarette Flavor product range — is essential for serving this audience.

4.3 The Regulation-Navigating Vaper

In jurisdictions with strict flavor bans — including several U.S. states, the UK under certain interpretations of the TRPR, and parts of the EU — some vapers pivot to unflavored bases as a regulatory workaround. Flavored e-liquids may be restricted, taxed differently, or require retail authorization that is not easily obtained.

This is not a fringe behavior. Mordor Intelligence’s 2026 market analysis identifies flavor regulation as a key structural driver pushing consumers toward unflavored and tobacco-flavored product alternatives. As flavor bans proliferate, this archetype will grow in proportion.

4.4 The Flavor-Fatigued Veteran

Long-term vapers — those with three or more years of daily use — frequently report experiencing “vaper’s tongue,” a temporary or semi-permanent desensitization of olfactory receptors to specific flavor molecules. When every flavor begins to taste muted or identical, many veteran vapers retreat to an unflavored base as a palate cleanser or permanent preference.

This phenomenon has a straightforward physiological explanation: olfactory receptor cells exhibit adaptation when exposed to the same chemical stimuli repetitively. Without the novelty of new flavors to stimulate engagement, the base liquid’s inherent textural and thermal properties become the primary points of sensory focus.

4.5 The Nicotine-Only User

Some vapers use unflavored base specifically to manage nicotine intake without any additional sensory engagement. This group includes former heavy smokers who associate the throat hit of high-PG, high-nicotine base with the physical sensation of cigarette smoking, and who find flavored alternatives either distracting or artificially sweet.

For this archetype, vaping is purely functional: a nicotine delivery mechanism, not a hedonic experience. Unflavored base at 18–36 mg/mL freebase nicotine with a high PG ratio most closely replicates the physiological sensation of traditional cigarette smoking.

4.6 The Industry Tester

Product developers, flavor chemists, and quality control professionals across the e-liquid industry regularly vape unflavored base as part of professional practice. When evaluating a new device, testing a coil configuration, or assessing wicking performance, a neutral base eliminates flavor variables from the test protocol, allowing for clean, reproducible assessments.

This professional use-case represents a small but economically significant demand stream, particularly for manufacturers producing high-purity, certified-grade base liquids.

Flavored vs Unflavored Vaping

5. The Scientific Evidence: What Research Says About Unflavored Vaping

5.1 Reduced Chemical Complexity Does Not Equal Safety

A common misconception in the unflavored community is that fewer ingredients automatically means greater safety. The science is more nuanced. While it is true that the absence of flavor compounds eliminates a layer of chemical complexity, PG and VG are not chemically inert under vaporization conditions.

A comprehensive 2025 study published in Toxicology Letters (Elsevier) titled “Toxicity of Humectants Propylene Glycol and Vegetable Glycerin in E-cigarette Aerosols” demonstrated that PG/VG aerosols — even without nicotine or flavoring — can induce oxidative stress, airway inflammation, and dysfunctional mucus secretion in airway epithelial cell models. The severity of effects was correlated with PG/VG ratio and vaporization temperature, with higher PG ratios and temperatures producing more adverse outcomes.

This does not invalidate the unflavored approach, but it underscores that base liquid quality, purity, and PG/VG ratio selection are not trivial choices — they have direct implications for the safety profile of the aerosol.

5.2 The Flavoring Additive Safety Argument

The strongest scientific argument in favor of unflavored vaping relates to the known and potential hazards of specific flavoring compounds. Research published in Environmental Science & Technology and other peer-reviewed journals has documented the following concerns with common flavor additives:

• Diacetyl and acetyl propionyl (used in butter and cream flavors): Linked to bronchiolitis obliterans (“popcorn lung”) at occupational inhalation exposures; present in many commercial e-liquids at detectable levels.
• Benzaldehyde (cherry/almond flavors): Cytotoxic to human bronchial epithelial cells at concentrations achievable in standard e-liquid formulations.
• Cinnamaldehyde (cinnamon flavors): Shown to reduce ciliary beating in airway epithelia, potentially impairing mucociliary clearance.
• Menthol and menthone (mint flavors): Associated with increased nicotine uptake and reduced quitting motivation, as well as airway dryness and sensitization.

In this context, the unflavored vaper’s logic is scientifically coherent: by eliminating all flavor additives, they eliminate the principal source of known and suspected inhalation toxicants in commercial e-liquids. Whether the residual risk from PG/VG alone is acceptable is a separate risk-benefit question — but the argument from hazard reduction is valid.

5.3 Comparative Aerosol Composition Studies

Multiple comparative aerosol studies — including research from the University of California San Francisco and the Roswell Park Comprehensive Cancer Center — have found consistently that unflavored e-liquids produce aerosols with lower concentrations of carbonyl compounds (acetaldehyde, formaldehyde, acrolein) compared to flavored counterparts at equivalent vaping parameters. The reduction in carbonyls is attributed primarily to the absence of thermally labile flavor molecules that serve as precursors for carbonyl formation.

This body of evidence has been acknowledged in regulatory frameworks: the FDA’s technical review of PMTA submissions has noted that the composition of flavorants is a significant variable in aerosol toxicant profiles, lending scientific credibility to the unflavored segment’s health rationale.

6. Regulatory Landscape: How Laws Are Shaping the Unflavored Segment

6.1 United States: FDA, PMTA, and Flavor Policy

The U.S. regulatory environment is arguably the single largest external driver of the unflavored market. Under the Family Smoking Prevention and Tobacco Control Act (TCA), all e-liquid products require FDA authorization for continued sale. The FDA has issued marketing denial orders (MDOs) to the vast majority of flavored e-liquid applications, citing insufficient evidence that the flavors’ appeal to adults outweighs their appeal to youth.

As a consequence of this regulatory pressure, the e-liquid market has experienced significant flavor consolidation. According to the CDC Foundation’s 2024 Monitoring E-Cigarette Trends in the United States Report, flavored e-cigarette sales decreased by 67.7% in California following the state’s statewide flavored tobacco policy, with a further reduction of 79.1% in the year after full enforcement. This creates direct displacement demand for unflavored alternatives in regulated markets.

6.2 European Union: TPD2 and National Flavor Restrictions

Under the EU Tobacco Products Directive (TPD2/2014/40/EU), e-liquids containing characterizing flavors other than tobacco are restricted or banned in several member states. The Netherlands, Finland, and Estonia have implemented particularly strict flavor restrictions, while the EU is conducting ongoing review of whether a harmonized flavor ban should be adopted across all 27 member states.

For manufacturers operating in EU markets, unflavored base liquids occupy a strategically important position: they are not subject to the same notification and prohibition requirements as flavored products, potentially simplifying market access.

6.3 China: GB Standards and STMA Oversight

China’s domestic e-cigarette market is regulated under the GB 41700-2022 National Standard and supervised by the State Tobacco Monopoly Administration (STMA). The standard mandates that only approved flavor compounds may be used in e-liquid formulations, and prohibits the addition of flavorings designed to appeal to minors. Unflavored base liquids, while not the dominant product format in China’s consumer market, are commonly used in OEM production environments for clients exporting to regulated international markets.

7. The DIY Base Culture: Community, Practice, and Economics

7.1 The Economics of DIY Base Vaping

From a pure cost perspective, DIY base vaping is substantially more economical than purchasing pre-mixed e-liquids. Consider the following comparison:

These economics create a powerful incentive structure. Experienced vapers who understand formulation are strongly motivated to purchase bulk unflavored base, separate high-concentration nicotine shots, and individual flavor concentrates, then mix to specification. The flavor concentrate market — both retail and wholesale — benefits directly from this behavior.

7.2 The Steeping Process and Base Chemistry

A distinctive practice within the DIY base community is “steeping” — the deliberate aging of a mixed e-liquid (base + concentrate + nicotine) over a period of days to weeks. During steeping:

• Ester compounds in flavor concentrates complete esterification reactions with PG molecules, producing more complex, rounded flavor profiles.
• Volatile top notes dissipate, shifting the sensory balance toward deeper base and mid notes.
• Oxidation of PG and any unsaturated compounds proceeds slowly, subtly altering flavor character.

Understanding the chemistry of steeping is directly relevant to flavor concentrate formulation. Concentrates designed for DIY applications must be engineered for post-mixing stability — a consideration that CUIGUAI Flavoring addresses through accelerated aging testing at 40°C and GC-MS vapor-phase analysis in our quality control protocols. For a deeper exploration of flavor stability and aging chemistry, we recommend our technical guide: Why Vape Flavor Fades Over Time (And How to Prevent It).

8. What the Unflavored Movement Means for Flavor Manufacturers

8.1 The Paradox: Base Vapers Drive Concentrate Demand

Counterintuitively, the growth of unflavored base vaping is not a threat to flavor concentrate manufacturers — it is a driver. The vast majority of base-only vapers who fall into the DIY archetype (Section 4.2) purchase flavor concentrates separately and in significant volumes. They represent a high-frequency, brand-loyal customer segment for concentrate suppliers.

For B2B flavor manufacturers serving OEM e-liquid brands, understanding the base-only segment informs product development priorities. DIY-oriented flavor concentrates must exhibit:

• High purity and consistent concentration accuracy (DIY mixers are precise formulators)
• Excellent PG/VG solubility across a range of ratios
• Thermal stability through a realistic range of coil temperatures (150–300°C)
• Long shelf life under proper storage conditions (12–24 months minimum)
• Clear usage rate documentation and mixing guidelines

8.2 Base Liquid Quality as a Brand Differentiator

For manufacturers producing unflavored base as a standalone commercial product, quality parameters become the primary competitive differentiator. In the absence of flavor, consumers can more readily detect impurities, off-notes, or viscosity inconsistencies. Key quality indicators for commercial base liquids include:

At CUIGUAI Flavoring, our electronic cigarette flavor concentrates are formulated for seamless integration into both pre-mixed e-liquids and DIY base applications. Our full electronic cigarette flavor product range includes fruit, menthol, tobacco, dessert, and beverage profiles — all formulated to meet international regulatory standards and designed for PG/VG base compatibility.

8.3 Implications for Product Line Strategy

The unflavored movement has concrete implications for e-liquid brand strategy. Brands operating in markets with increasing flavor restrictions have several strategic options:

• Invest in high-quality unflavored base as a standalone product line for health-conscious consumers.
• Develop certified DIY concentrate kits that pair unflavored base with curated flavor options, maintaining consumer engagement while adapting to regulatory constraints.
• Leverage unflavored base as a testing platform for new device hardware before flavored product launches.
• Position unflavored base as a “premium purity” product at a modest price premium, targeting the health-conscious minimalist archetype.

9. The Future of the Unflavored Segment: Trends and Predictions

9.1 Regulatory Consolidation Will Grow the Segment

The trajectory of global vaping regulation points toward increasing flavor restriction, not relaxation — with the notable exception of recent FDA authorizations of specific fruit-flavored products (May 2026). The structural pressure from multi-market flavor bans will continue to redirect consumer spending toward either unflavored alternatives or compliant flavored products that survive regulatory review.

For unflavored base manufacturers, this represents a long-term demand tailwind. Brands that build early capability in high-quality, certified base liquid production will be strategically positioned as regulatory environments continue to evolve.

9.2 Natural Base Innovations

A growing sub-segment of the unflavored market is interested in “naturally derived” base liquids — PG derived from bio-based feedstocks, or VG certified as organic and non-GMO. As consumer health consciousness intensifies, the provenance and certification of base ingredients will become increasingly important purchasing criteria.

Manufacturers who can provide certified organic VG, allergen-free PG, and documented supply chain transparency will enjoy competitive advantages in premium market segments.

9.3 The Intersection of Unflavored and Nicotine-Alternative Products

The emergence of synthetic nicotine, nicotine salts, and non-nicotine stimulant alternatives (such as caffeine or adaptogenic compounds) is creating new categories of base-only products that do not fit neatly into existing flavor-focused frameworks. These products share the structural simplicity of unflavored base while targeting specific physiological effects.

This convergence of clean-base formulation and functional ingredient integration represents one of the most dynamic frontiers in e-liquid product development — a space where flavor chemistry expertise, regulatory navigation, and base liquid science intersect.

9.4 The Professional DIY Market Matures

The DIY e-liquid community is maturing rapidly. Early adopters who mixed simple two-component blends have become sophisticated formulators capable of recreating complex, layered flavor profiles. As this community grows and its technical sophistication increases, demand for professional-grade flavor concentrates — precisely dosed, analytically verified, and formulated for vaping applications — will intensify.

This maturation creates significant opportunity for flavor concentrate manufacturers who position themselves as trusted technical partners to the DIY community, rather than merely product suppliers. CUIGUAI Flavoring’s R&D-led approach to flavor development — including GC-MS analytical verification and toxicological review — is directly aligned with this market direction. For a comprehensive overview of flavor profiles and formulation principles, see our resource: Complete Guide to E-Liquid Flavor Profiles and Applications.

10. Conclusion: The Unflavored Movement Is a Signal Worth Heeding

The “unflavored” movement in vaping is not a symptom of market failure or consumer indifference — it is a coherent, multi-dimensional phenomenon driven by regulatory pressure, scientific awareness, economic incentives, and behavioral psychology. Its growth from a niche curiosity to a statistically measurable market segment with a 9.35% CAGR signals that it deserves serious attention from every stakeholder in the e-liquid value chain.

For flavor concentrate manufacturers, the unflavored segment is a companion market, not a competitor. Its growth drives concentrate demand through the DIY channel, raises the bar for base liquid quality standards, and creates new product development opportunities at the intersection of purity, functionality, and regulatory compliance.

At CUIGUAI Flavoring, we view the unflavored movement as evidence that the vaping industry is becoming more sophisticated — and that sophisticated markets demand sophisticated supply chain partners. Whether you are formulating for the health-conscious minimalist, the professional DIY mixer, or the regulation-navigating brand, the foundation of your product is the base — and the quality of your base determines the quality of your vaping experience.

The flavor doesn’t begin when you add a concentrate. It begins with the purity of the base itself.

Vape Flavor Lab CUIGUAI

— Partner With CUIGUAI Flavoring —

Technical Exchange & Free Sample Request

Whether you are developing a new unflavored base product line, sourcing flavor concentrates for DIY distribution, or evaluating OEM e-liquid flavor solutions for international markets — our R&D team is ready to support your project from concept to compliance.

Website: www.cuiguai.com

Email: info@cuiguai.com

Phone: +86 0769 8838 0789

WhatsApp & Telegram: +86 189 2926 7983

Address: Room 701,Building C,No.16,East 1st Road,Nange,Binchong,Daojiao Town,Dongguan City, Guangdong Province, China

Free sample shipment available to qualified B2B buyers. NDA support provided. Contact us today.

References & Authority Citations

[1] U.S. Centers for Disease Control and Prevention (CDC). “Outbreak of Lung Injury Associated with the Use of E-Cigarette, or Vaping, Products.” 2019. Available at: cdc.gov/tobacco/e-cigarettes.

[2] CDC Foundation. “Monitoring E-Cigarette Trends in the United States Report.” November 21, 2024. Available at: cdcfoundation.org.

[3] Mordor Intelligence. “E-Liquid Market Size, Share & 2031 Growth Trends Report.” 2026. Available at: mordorintelligence.com.

[4] National Institutes of Health (NIH) / PubMed. “The Impact of E-liquid Propylene Glycol and Vegetable Glycerin Ratio on Aerosol Formation.” Aerosol Science and Technology, Taylor & Francis, 2020. PMC ID: PMC7171278.

[5] Elsevier. “Toxicity of humectants propylene glycol and vegetable glycerin in e-cigarette aerosols.” Toxicology Letters, 2025. doi: 10.1016/j.taoxlet.2025.

[6] U.S. Food and Drug Administration (FDA). “E-Cigarettes, Vapes and Other Electronic Nicotine Delivery Systems (ENDS) Authorized by the FDA.” May 2026. Available at: fda.gov.