Curly hair is a natural beauty that many people aim to achieve through specific treatments and products. However, there is a significant difference between natural and artificial curls.
Natural curls are the result of a natural curvature of the hair follicles, making the hair more likely to become curly or wavy. This natural curvature is genetically determined, meaning that natural curls are present from birth.
On the other hand, artificial curls are created through special treatments and products, such as curlers, permanent waving, or curl-defining products. These treatments and products can help create and maintain curls, but can also damage the hair if not used correctly.
Moreover, natural and artificial curls require different care and products to maintain their health. Natural curls tend to be drier and more fragile than straight hair, which requires particular attention in the selection of products and treatments. Artificial curls may require a greater use of products to maintain the shape of the curls.
If you wish to achieve or maintain your curly hair, you can choose the right products for you through a wide selection of specific hair care products for curly hair. By choosing the right products, you can enjoy beautiful and healthy curls, whether they are natural or artificial.
Molecular Differences Between Natural and Artificial Curls
Natural curls result from an asymmetric distribution of disulfide bonds (S–S) in the cortex, genetically encoded in follicle morphology. The ortho- and paracortical zones — the two distinct regions of the cortex — contain different proportions of high-sulfur (HS) and low-sulfur (LS) proteins, creating a differential expansion force that curves the fiber during keratinization. This curvature is permanent and resistant to mechanical straightening: the internal S–S bond distribution re-asserts itself as soon as the mechanical constraint is removed.
Artificial curls created by perming operate through chemical reduction-oxidation of those same S–S bonds: ammonium thioglycolate (pH 9–9.5) breaks disulfide bonds by reduction, allowing the fiber to be reformed around a curl rod, before hydrogen peroxide reoxidizes the bonds in the new configuration. The resulting curl is chemically stable but structurally more fragile than a natural curl: the cortex has been oxidized and the cysteine content partially degraded, resulting in higher differential porosity and greater sensitivity to hygral fatigue (repeated hydration-dehydration cycles).
Formulation Implications for Each Curl Type
Natural curls require formulations that compensate for the sebum distribution deficit caused by curvature (emollients, butters, fatty alcohols) and define the curl without weighing it down (light film-forming polymers, cationic polyquaterniums). Artificial curls require post-chemical care focused on protein repair (hydrolyzed keratin 300–5,000 Da), bond reinforcement and prevention of hygral fatigue — a protocol distinct from daily curl maintenance.
Professional Product for Natural and Artificial Curls
For professionals working with natural or permed curls, the Twisting Fluid by Nika, available on cliCHair.ch, is a leave-in formulation based on cationic film-forming polymers and glycerin. It defines the curl without weighing it down, maintains the acquired curvature angle, and reduces frizz by depositing a light hydrophobic film on the cuticle — a mechanism consistent with the hair fiber curvature chemistry analyzed in this article.