Thermal Hair Styling: Evolution and Risks

Thermal Hair Styling, an early hair grooming technique, involved using heated iron rods and curling pads made of metallic plates to wrap hair fibers around for styling and management.¹

Despite the promising results, this ancient method had the drawback of exposing hair, scalp, and consumers to hot metallic rods. However, over the years, advancements were made to improve the equipment and address safety concerns, resulting in more user-friendly techniques.

Today, curling rods, flat irons, and blow dryers are commonly used by consumers from all walks of life. While these tools offer benefits like hair styling, grooming, and improved manageability, they also pose a risk of damaging hair fibers. The high temperatures generated by these heat styling tools lead to significant changes in the hair fiber’s structure, ultimately harming hair quality.

Signs of Heat Damage to Curly Hair

When hair fibers undergo excessive heat processing, clear signs of damage become evident on their surface. Some of these telltale signs include the following:

• Dryness
• Rough texture
• Broken strands
• Split ends
• Increased (high) hair porosity
• Loss of defined curl shape
• Heightened susceptibility to breakage during combing and brushing
• Lackluster strands
• Lack of shine
• Severe damage may lead to irreversible changes in the curl pattern

A closer look through microscopic analysis confirms that heat not only compromises the surface smoothness but also leads to the rupture of the fiber structure itself.

Understanding Heat-Induced Damage to Hair Fiber: Unraveling the Effects of Heat

Hair, a remarkable protein-based fiber, boasts a complex structure consisting of three distinct layers. The outermost layer, known as the cuticle, plays a crucial role as it is the first line of defense exposed to the outside environment. The cuticles align meticulously, forming a smooth and orderly surface. This alignment is pivotal for controlling surface friction, roughness, and porosity.

However, when subject to thermal styling with temperatures exceeding 200 degrees Celsius, the hair protein undergoes degradation, resulting in permanent changes to its structure. These alterations impact the mechanical strength, cosmetic attributes, and overall texture of the hair fiber. ^2,3,4

Moreover, the application of heat during styling causes the removal of water from the hair’s surface. The heat energy effectively evaporates the hair’s natural moisture content, causing water molecules to escape from the cuticle surface.

Under high-energy conditions, steam formation beneath the cuticle layer creates bumps or irregularities on the surface, leading to abrupt rupture and breakage. These changes seriously jeopardize the integrity of hair fibers, ultimately contributing to hair breakage. Microscopic examination of heat-processed hair fibers reveals the presence of these bumps or chips, underscoring the impact of heat on the delicate hair structure. ^5–6

How To Restore Curls After Heat Damage: Key Ingredients

To restore the natural texture and body of heat-damaged hair fibers, a tailored hair care regimen is essential. Here are some key aspects to consider when repairing heat-damaged hair:

Hydration

Water is the lifeblood of hair. Heat processing depletes the hair’s water content, resulting in dry, rough, and brittle strands. Localized steam formation during heat styling can damage the cuticle layer and alter the surface properties, making hair difficult to comb, brush, and style. Therefore, it is crucial to replenish and maintain the moisture level of the hair fibers.

Look for hair care products that contain humectants and hydrating agents to help lock in moisture. Additionally, avoid using products that contain drying alcohols (e.g., ethyl alcohol) or chemicals like SLS (sodium lauryl sulfate) and sodium hydroxide, as they can further dry out the hair fibers.

Our recommended humectants and hydrating ingredients are:

1. Vegetal Glycerin
2. Propylene Glycol
3. Propanediol
4. Sodium PCA or Zinc PCA
5. Betaine
6. Panthenol
7. Aloe Vera Juice or Gel
8. Ceramides
9. Alpha Hydroxy acids preferably Lactic acid and Sodium Lactate

Emollients

Emollients play a vital role in preserving the loss of water molecules from the hair surface. These hydrophobic liquids create a water-resistant layer, effectively minimizing water escape.

When it comes to emollients, natural options are highly favored due to their multifunctional benefits, environmentally friendly origin, and sustainable supply chain.

For an effective hair care routine to restore heat-damaged hair fibers, deep conditioning products such as rinse-off conditioners, deep conditioning masks, and leave-in conditioners should incorporate these natural emollients.

Not only do they improve the quality of heat-damaged hair fibers, but they also enhance the overall sensorial texture and reduce dryness after application.

Among the array of options, our selected and preferred natural emollients for heat-damaged hair fibers include:

1. Shea Butter
2. Cocoa Butter
3. Mango Seed Oil
4. Babassu Oil
5. Coconut Oil
6. Apricot Kernel Oil
7. Meadowfoam Seed Oil
8. Baobab Oil

The most effective approach is to find a formulation that combines two to three different oils or butter. The dosage of each ingredient will vary based on the specific formulation. For a deep conditioning mask to yield optimal results, it should contain a medium to high dosage of these oils or butters.

Proteins and Amino Acids

Proteins and related amino acids are powerful active ingredients that work wonders on both the cuticle surface and inner cortical structures of the hair.

Large molecular protein fragments create a water-friendly coating on the surface, while smaller amino acids can penetrate the cuticle layer and fill the empty ruptured sites. This process leads to improved surface smoothness and, thanks to their hydrophilic properties, proteins also boost fiber moisture levels.

Here are some preferred protein actives for your consideration:

1. Hydrolyzed Wheat Protein
2. Hydrolyzed Keratin
3. Hydrolyzed Wheat Amino Acids

Silicones

Silicones are versatile materials known for their remarkable surface coating properties and water repellency. Among them, silicone oils stand out as excellent surface smoothening agents, effectively reducing cuticular friction and minimizing fiber-to-friction damage.

The remarkable stability of silicone oils prevents any degradation or molecular breakdown even under heat exposure, making them ideal for providing excellent heat protection to hair fibers during blow drying and flat ironing. By incorporating a small dosage of silicone oils, hair proteins can be preserved, and the adverse effects of excessive heating can be minimized.

Here are some key heat-protecting silicones to consider:

1. Dimethicone
2. Cyclomethicone
3. Cyclopentasiloxane
4. Phenyltrimethicone

Note: There is nothing wrong with using silicones as long as they are used in small dosages and low frequency. However, to prevent silicone build up on the hair shaft, it is advisable for consumers to use an anti-residue clarifying shampoo occasionally when washing their hair. This ensures that silicones are effectively removed and helps maintain the health and appearance of the hair.

How Long Does it Take to Repair Heat Damaged Hair?

The process of repairing damaged hair fibers is not a quick fix; it demands a comprehensive strategy to restore their surface quality, shine, texture, and body.

Alongside using good-quality and customized hair care products, achieving success requires a well-thought-out day-to-day hair care routine, consistency, dedication, and commitment. There is no magical one-size-fits-all product to solve the problem.

It’s essential to experiment with different products and find what works best for your hair. Most importantly, keep it simple and focus on the basics. This approach ensures a cost-effective yet effective hair care regimen.

Below are some key tips to serve as a basic guideline in your hair restoration journey.

Key Tips to Prevent Damage

• Prevention is key: Minimize heat processing to protect your hair from damage.
• Opt for air drying instead of hot air when blow drying your hair.
• When using a flat iron, choose a low heat setting to avoid excessive damage.
• Always apply a heat protector before blow drying or flat ironing to shield your hair from heat-related harm.
• Use a mild and gentle shampoo for regular hair washing, avoid excessive use of ingredients like Sodium Lauryl Sulfate (SLS) that can cause dryness.
• Choose a shampoo that combines mild surfactants, conditioning ingredients, and hydrating agents (some listed above) for optimal hair care.
• After shampooing, promptly apply a hydrating conditioner to facilitate detangling and ease wet and dry combing.
• Make leave-in conditioner your go-to product for outdoor activities, as it should contain emollients, hydrating agents, and fiber-softening actives while offering protection against UV radiation.
• Once a week, use an anti-residue clarifying shampoo to prevent any product build-up on your hair.
• Consider a protein treatment once every two weeks to strengthen and revitalize your hair.

FAQs

What Temperature Is Right For Straightening Your Hair?

The ideal temperature for straightening curly hair depends on your hair type and texture. As a general guideline, it’s recommended to use heat styling tools, such as flat irons, at temperatures between 300°F to 375°F (approximately 150°C to 190°C).

Lower heat settings are more suitable for fine hair, while thicker and coarser hair may require slightly higher temperatures. Always start with the lowest heat setting and gradually increase if needed, and never exceed 400°F (about 200°C) to minimize the risk of heat damage.

Should You Use Heat Styling Tools Again?

Using heat styling tools should be done sparingly, especially if your hair is prone to damage or if you’ve recently experienced heat-related issues. Frequent heat styling can lead to cumulative damage over time, causing brittleness, breakage, and a loss of natural curl pattern. Whenever possible, opt for heatless styling methods, such as air-drying, twist-outs, or braid-outs, to give your curls a break from excessive heat exposure.

Does Heat Permanently Damage Hair?

Yes, heat can cause permanent damage to hair. When hair is exposed to high temperatures, the protein structure and moisture content of the hair fibers can be altered. This leads to weakened and dehydrated hair, resulting in reduced elasticity and an overall compromised hair structure. While some heat damage can be repaired through intensive hair care and nourishing treatments, severely damaged hair may require trimming or cutting off the affected portions.

Is it Best to Cut off Damaged Hair?

In many cases, cutting off damaged hair is the best course of action to promote healthy hair growth and restore the natural curl pattern. Trimming or cutting off the damaged ends prevents further splitting and breakage, allowing the hair to grow back stronger and healthier.

Regular trims every 6 to 8 weeks can gradually remove damaged hair while retaining the overall length. Embracing a shorter style, such as a curly bob or pixie cut, can be a practical and stylish way to manage and regrow healthy curls.

However, the decision to cut off damaged hair ultimately depends on the severity of the damage and your personal hair goals. Consulting a professional stylist can provide valuable insights and recommendations tailored to your specific hair needs.

Summary

Heat-damaged curly hair fibers suffer from dryness, brittleness, and roughness, making them challenging to style and manage in our daily grooming routine.

To bring back their natural beauty, shine, texture, and body, a comprehensive and personalized hair care regimen is essential.

Reducing heat exposure and minimizing the use of thermal styling techniques is highly recommended. By carefully selecting suitable hair care products and creating a dedicated hair care routine, we can effectively address thermal damage and restore the overall health of our hair.