A hair care formulation is a carefully crafted mixture of various ingredients designed to achieve specific results. These ingredients can be either synthetic, manufactured through chemical processes, or derived from natural sources such as plants.
Plant-based ingredients, including extracts from fruits, flowers, seeds, bark, oils, and butters, are particularly popular. They are valued for being sustainable and environmentally friendly, offering a “green” alternative to synthetic components. Due to their natural origins, these ingredients are often marketed as being gentler and safer for the hair, scalp, and skin. They are frequently discussed in media outlets, social media, and online blogs, which tout their benefits over synthetic ingredients.1,2,3
However, the safety of these natural ingredients is not always guaranteed. Reports have indicated that repeated exposure can lead to contact dermatitis, raising concerns about their mildness and safety.4 Like synthetic ingredients, natural ingredients also contain active chemical compounds.
To provide a deeper understanding, I have consulted with a hair scientist and cosmetic formulator who holds a PhD in Chemistry. This expert will help explain the science behind natural ingredients used in hair care products, assess their safety, and clarify their effects on the scalp and skin.
Additionally, we will explore the appropriate use of hair care products containing high concentrations of natural ingredients, discussing their safety in comparison to synthetic options. This thorough examination aims to equip you with the knowledge to make informed decisions about the products you choose for your hair care regimen.
Definition of “Natural” in Cosmetics
The term “natural” in cosmetics often lacks a clear and universally accepted definition. Generally, natural ingredients are those derived, obtained, or extracted from plant-based materials. These ingredients are used to enhance appearance and promote healthier skin or hair.
However, regulatory bodies, cosmetic scientists, and marketing experts do not agree on this definition. The main issue is determining which ingredients qualify as natural, even if they are derived from plant sources. Different organizations have their own standards for classifying a material as natural, leading to varied interpretations and standards across the industry.
To simplify, our definition of natural ingredients is materials derived from plants or their parts, which are processed minimally enough to retain their natural physical, chemical, and biological properties. This approach aims to provide a clearer understanding while acknowledging the complexities within the cosmetic industry
Definition of Synthetic Ingredients
To better understand what constitutes natural ingredients, let’s explore their counterparts: synthetic ingredients. Synthetic ingredients are man-made materials created in laboratories. They begin with a basic carbon chain molecule to which various chemical groups are attached, building larger, complex molecules.
This method is commonly used in the production of medicines and drugs, where molecules are specifically synthesized to deliver certain properties or benefits. Essentially, synthetic ingredients are designed to achieve targeted results through precise chemical engineering. This process contrasts with natural ingredients, which are derived more directly from plant or other natural sources with minimal processing.
Understanding “Chemical” and “Natural” in Hair Care
The curly hair community is often concerned about “chemicals” in hair care products, prompting many to seek natural alternatives. However, the term “chemical” is often misunderstood and misused. Contrary to popular belief, not all chemicals are harsh, unsafe, or cause adverse effects on skin and hair.
In essence, a chemical is any substance composed of elements like hydrogen, oxygen, carbon, and potassium, with a specific composition. Chemicals can be either natural or synthetic. For example, water, which is a natural ingredient, is also a chemical known scientifically as dihydrogen oxide.
Water, the universal solvent, forms a major component of most hair care products. Imagine if a product label listed “dihydrogen oxide” instead of water—studies show that consumers might react negatively despite it being the same familiar substance.
Similarly, many natural ingredients are chemicals produced through complex reactions in plants. Sugar, for example, is a chemical naturally produced and stored in fruits. Whether sugar is sourced from plants or synthesized in a lab, its chemical composition and properties remain the same.
Even olive oil, a natural emollient widely used in hair and scalp care products, is both a natural product and a chemical ingredient.
It’s important to realize that chemicals are not inherently dangerous. They are extensively used in various life sciences applications and their safety is determined by their chemical structure, dosage, and exposure level.
A thorough understanding of toxicology and safety assessments is crucial to determine their compatibility with human skin, tolerance, and potential for irritation or erythema. Thus, while the word “chemical” might seem scary, these substances are essential and often beneficial components of many products.
Are Natural Ingredients Safer Than Synthetic?
It’s a common misconception that natural ingredients are inherently safer than synthetic ones. However, like synthetic ingredients, natural ingredients must be rigorously tested for safety and skin compatibility.
Natural ingredients can also pose risks, such as skin sensitization and adverse reactions upon topical application. There have been numerous instances where ingredients derived from natural sources have shown poor safety profiles and triggered negative skin reactions.
The safety and toxicity of any ingredient are primarily dependent on its chemical composition and the dosage used. This critical factor is often overlooked. Natural ingredients usually consist of a mixture of different chemical components, which can vary widely in their properties.
For example, aloe vera extract combines polysaccharides with different chemical characteristics. Similarly, hydrolyzed wheat protein comprises various amino acids with differing molecular weights. The composition of natural ingredients can fluctuate significantly due to seasonal changes, cultivation practices, harvest timing, and processing methods.
These variations present a significant challenge for using natural ingredients consistently, as their chemical makeup is not fixed. Cosmetic formulators and chemists must work closely with manufacturers and suppliers to ensure that natural ingredients have a consistent chemical composition over time.
Moreover, natural ingredients are susceptible to oxidation and microbial contamination. When exposed to air and light, natural molecules can undergo autoxidation, leading to free radical reactions that compromise their stability for use in hair care products. This instability can potentially harm the skin and hair.
Microbial contamination, on the other hand, can cause malodors, discoloration, and even alter the microbiology of the scalp or skin. It is crucial for the cosmetic formulation process to assess the stability and microbiology of each natural ingredient before inclusion in a product.
Manufacturers and suppliers should provide a certificate of analysis to guarantee the quality of each batch, as there have been documented cases of microbial contamination rendering natural ingredients unsuitable for use.5
Dosage Sensitivity: Understanding Exposure Levels
The safety and toxicity of any ingredient, whether synthetic or natural, significantly depend on its dosage and the extent of exposure to the skin or scalp. Simply put, this refers to how much of the substance the skin can tolerate and for how long.
Regulatory bodies such as the FDA in the United States and similar organizations in Europe have published reports that detail the safety, toxicity, and concentration limits of various ingredients for different types of applications. These guidelines apply equally to both synthetic and natural ingredients.
It is crucial not to use any ingredient indiscriminately without considering the appropriate dosage and duration of contact with the scalp, hair, or skin. For example, sodium chloride, commonly used in hair care products to adjust viscosity, can cause skin irritation, redness, and sensitization if applied directly in high concentrations.
The principle that “excess of everything is bad” also applies to natural ingredients. Using a natural ingredient in excessive amounts or leaving it on the hair or scalp for an extended period may not be beneficial and could lead to adverse reactions, damaging both the hair fibers and the scalp. It is essential to adhere to recommended usage guidelines to ensure safety and effectiveness.
Practical Examples: Essential Oils
Essential oils are complex blends of organic molecules extracted from various plants. They are distinct from natural oils, which are primarily long fatty acid esters. Known for their characteristic aromas and therapeutic properties, essential oils enjoy widespread popularity for their diverse benefits.
However, it is important to note that essential oils can also sensitize the skin and scalp. Tea tree oil, for instance, is celebrated for its skin benefits but has undergone extensive clinical testing to assess its safety. The European Scientific Committee on Consumer Safety (SCCS) has published a report on tea tree oil, identifying it as a potential skin sensitizer.
Accordingly, specific concentration limits are recommended for its use: no more than 2.0% in hair care products and 1.25% in skincare products. This highlights the necessity of adhering to safety guidelines to prevent adverse reactions when using essential oils in consumer products.6,7,8
Summary
Natural ingredients are favored in hair care due to their eco-friendly origins, sustainable sourcing, and minimal carbon footprint. However, it’s crucial to recognize that these ingredients are not inherently safe simply because they are natural. They require the same rigorous safety evaluations as synthetic ingredients.
Despite common beliefs among consumers that natural ingredients are automatically safe, this assumption is not scientifically supported. Regulatory bodies like the FDA and the EU have clearly stated that all ingredients, regardless of their source, must be thoroughly assessed for safety before being used in hair care, skin care, or other cosmetic applications. This ensures that products are safe for consumer use and meet strict safety standards.
References
- Mellou, F.; Varvaresou, A.; Papageorgiou, S., Renewable sources: applications in personal care formulations. International Journal of Cosmetic Science 2019, 41 (6), 517-525. ↩︎
- Burlando, B.; Verotta, L.; Cornara, L.; Bottini-Massa, E., Herbal Principles in Cosmetics: Properties and Mechanisms of Action. CRC Press: 2010. ↩︎
- Dweck, A. C., Formulating Natural Cosmetics. Allured Business Media: 2011. ↩︎
- Chandon, L., Do Claims about the Naturalness and Dose of Cosmetics Ingredients Affect the Public’s Perception of Their Safety? J 2020, 3 (3), 23. ↩︎
- Bozzi, A.; Perrin, C.; Austin, S.; Vera, F. A., Quality and authenticity of commercial aloe vera gel powders. Food chemistry 2007, 103 (1), 22-30. ↩︎
- Goodier, M. C.; Zhang, A. J.; Nikle, A. B.; Hylwa, S. A.; Goldfarb, N. I.; Warshaw, E. M., Use of essential oils: A general population survey. Contact dermatitis 2019, 80 (6), 391-393. ↩︎
- Southwell, I. A.; Freeman, S.; Rubel, D., Skin irritancy of tea tree oil. Journal of Essential Oil Research 1997, 9 (1), 47-52. ↩︎
- SCCP, SCCP Opinion on Tea Tree Oil. Scientific Committee on Consumer Products: 2008. ↩︎
