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Dealing with brittle, broken hair strands and not sure why? Hair breakage is an issue that frustrates countless individuals, but the first step to fixing the problem is understanding its root causes.
When it comes to hair breakage causes, a few culprits are usually at play: Harsh chemical treatments, thermal and photodamage, hair styling accessories, and inadequate nutrient intake. Stay with us as we explore each of these factors in detail, arming you with the knowledge you need to make informed hair care choices.
Together with my hair scientist friend who has a PhD in Cosmetic Chemistry, we’re merging our expertise to provide you with science-backed insights. We’ll tackle the root causes (pun intended) of hair breakage, explore the factors that accelerate it, and offer guidance on how to control it effectively.
According to scientific research, many people who suffer from hair breakage see it as a clear indicator of inferior or poor hair quality.1
Let’s dive into the science for a moment: Hair is essentially a protein fiber with different morphological layers. The exterior or outermost layer, known as the cuticle, protects the inner core or cortex of the hair.3
Understanding these layers can provide valuable insights into how to tackle hair breakage effectively.
Both the cuticle and the cortex are primarily composed of the protein keratin rich in the amino acid cysteine, which contains sulfur. These amino acids are intricately bonded to create the unique keratin structure that defines hair. Understanding this structure helps us get to the core of hair health.
The strength and resilience of your hair largely depend on the chemical bonds that shape its keratin structure, specifically the disulfide bonds of cysteine—essentially, sulfur-to-sulfur bonds. These are crucial for maintaining the mechanical strength of the hair fiber.3
When these bonds are compromised, the structural integrity of the hair is affected, leading to fractures along the hair shaft.4
Now that you’re armed with this scientific insight, let’s explore some of the main factors contributing to hair breakage.
Brushing and combing your hair may seem like harmless everyday activities, but did you know they exert pressure on your hair strands, specifically the outer cuticle layer?
Using tools with plastic or wooden teeth can actually dislodge (loosen) or remove these protective cuticles. The force needed to glide a comb through your hair is often used scientifically to evaluate both the surface smoothness and mechanical strength of your hair fiber.
Brushing your hair too vigorously, especially with a narrow-toothed comb, increases friction and requires more force, making your hair more prone to surface damage.
This can lead to erosion of the cuticle layer, weakening the hair strands and making them more susceptible to breakage. You might even notice broken hair fibers on your comb or brush, a glaring red flag indicating damage.5,6
But here’s a science-backed tip: The amount of force needed to comb your hair changes depending on its condition. Studies have shown that wet hair requires more force to comb through.
Why? Water causes the hair strands to swell and the cuticle layers to expand. This expansion increases friction, making wet hair more vulnerable to breakage.7
When it comes to altering your hair’s natural state, whether it’s changing its color, curl pattern, or texture, chemical treatments are often the go-to solution.
These treatments, like hair coloring, perming, and straightening, use powerful compounds such as alkaline hydrogen peroxide, thioglycolic acid, sodium hydroxide, and guanidine hydroxide.
While these agents effectively bring about the desired changes, they also induce several chemical alterations that may not be so favorable for the health of your hair.
For example, in the bleaching process, alkaline hydrogen peroxide is used to strip away melanin and oxidize cysteine amino acids, effectively breaking the crucial disulfide bonds that give your hair its strength.
This results in a weakened protein structure and exposes the cuticle layer to potential damage. Studies indicate that chemically treated hair, such as bleached hair, is far weaker than untreated hair.
Consistent use of bleach or other harsh chemicals compounds the hair damage, making the hair more susceptible to breakage.2
So before you dive into another round of chemical treatments, it’s essential to weigh the pros and cons.
If you’re considering chemical treatments for your hair, it’s crucial to prioritize hair health alongside your aesthetic goals.
One science-backed tip is to incorporate a “protein-moisture balance” regimen before and after undergoing any chemical processes.
Strengthening treatments rich in proteins like keratin can help rebuild the disrupted protein structure while deep-conditioning treatments nourish dry hair by restoring essential moisture lost during chemical processing.
Further, be cautious with the frequency of chemical treatments. Overprocessing can accelerate damage to dry and brittle hair, weaken the structural integrity of the hair fibers, and worsen breakage.2
Research suggests that spacing out chemical treatments allows your hair to recover and rebuild its natural defenses.
Last but not least, always conduct a strand test before proceeding with any full-scale chemical treatment.
This not only helps you gauge the end result but also provides an initial assessment of how your hair will react to the chemicals, allowing you to adjust treatment parameters accordingly.
Thermal styling, such as using hot tools like a blow dryer, curling iron, and flat iron, is a popular method for shaping your hair. However, scientific research warns us that these techniques can actually damage the protein structure of your hair.
At elevated temperatures and excessive heat, hair proteins undergo a process called chemical denaturation, leading to both radial and longitudinal cracks in the hair fiber.
But heat isn’t the only culprit here; exposure to UV radiation from the sun can also wreak havoc on your hair.
Scientific studies indicate that UV radiation oxidizes hair proteins and generates highly reactive free radicals. These unstable molecules further oxidize the proteins, leading to protein loss.
If you frequently style your hair using heat or spend a lot of time in the sun, protecting your hair from thermal and photodamage is essential.
These sprays are often formulated with silicones or polymers, creating a protective barrier around each hair strand. This barrier not only reduces the direct impact of high temperatures on hair proteins but also helps to retain moisture.11,12
As for photodamage from UV exposure, consider using hair products that contain UV filters, similar to the ones found in sunscreens.
These filters can absorb or reflect UV radiation, minimizing its oxidative effects on your hair proteins.13 You could also wear hats or use physical barriers to shield your hair from direct sunlight.
Another tip is to do regular deep conditioning treatments which can also help restore the moisture balance and fortify the hair strand, making it less susceptible to both thermal and photodamage.
We all love to style our hair, but did you know that common hair accessories like rubber bands and curling rods can actually alter the structure of your hair shafts?
These styling tools can lead to curled knots, tangles, and twists, creating physical changes that make your hair more susceptible to breakage.
The damage inflicted by these accessories goes beyond surface-level issues; they can also affect the hair cuticle, the outermost layer of your hair strand, making it vulnerable to further damage.14
Over time, excessive use of such accessories can even impact your hair follicles and impede healthy hair growth, potentially leading to conditions like telogen effluvium, a form of temporary type of hair loss.15
Your type of hair and hair care routine can play a significant role in how your hair responds to these accessories. To delve deeper into this, let’s explore the solutions outlined below.
If you’re concerned about the damage caused by hair styling accessories, science offers a solution: focus on material and tension.
Curly or textured hair may be more prone to damage from tight hairstyles compared to straight hair. A low-tension hairstyle, which doesn’t pull on the follicles, can be a healthier alternative.
Additionally, these materials are less likely to pull or tug, which is essential for protecting your hair follicles and preventing conditions like telogen effluvium.
Inadequate nutrient intake can be a significant contributor to hair breakage.17 A diet lacking in essential nutrients such as folic acid can weaken the hair strands at a molecular level.
According to the American Academy of Dermatology, supplements including biotin and folic acid are said to help grow and thicken hair.18
To combat hair breakage due to nutrient deficiencies, consider incorporating foods rich in folic acid into your diet, such as leafy greens, oranges, and fortified cereals.
This can strengthen your hair from the inside out, giving it the structural integrity it needs to withstand external stresses.19
Always consult a healthcare provider for personalized dietary advice.
Recent scientific studies have highlighted that hair with tighter curls and smaller curl curvature tends to be more vulnerable to breakage.
For example, African-American hair often features a high degree of coiling and kinkiness. This unique texture makes it more fragile, and consequently, more susceptible to breakage, especially when exposed to forceful detangling or styling practices.24
In summary, hair that possesses a more curled or coiled structure is generally more prone to breakage when exposed to physical stressors like combing or brushing.
Being aware of your hair type can inform your hair care routine, helping you make smarter choices to protect your hair.
Here is a short list of signs that indicate hair breakage:
● Finding broken hair threads in your comb or other styling tools.
● Split ends at the tips.
● Random and disorganized curl pattern with the tips of the hair emerging from the curvature, pointing in random directions.14
Here are a few key steps to preventing hair breakage:
● Keep your hair and scalp clean – A healthy scalp is essential for healthy hair. It ensures nutrients and water molecules are available for active and healthy follicles. Wash your hair and keep them clean.
● Keep your hair conditioned – conditioning formulation reduces the fiber-to-fiber friction, lubricates the shaft, and controls the cuticle damage. To keep your hair healthy, it’s important to use a moisturizing conditioner regularly.
● Trim your ends – Regular trims or having a haircut removes the damaged tips.
● Avoid aggressive chemical treatments or at least limit their usage.
● Opt for hair-friendly styling tools and products – avoid using rubber bands, tight curl holders, etc. Instead, use hair accessories, such as satin scrunchies or spiral ties (these are my favorites!).
To prevent hair breakage, consider personalizing your hair care regimen with tailored shampoos, conditioners, or leave-in treatments.
These specialized products contain targeted ingredients designed to either strengthen or soften hair fibers.
By improving the surface properties of your hair, these products reduce friction, make detangling easier, and prevent the tangles that often lead to breakage.
A few ingredients are listed here:
Hair conditioners and treatments frequently utilize cationic surfactants, which are molecules with a positive charge. These surfactants form strong bonds with the protein residues in hair fibers due to their opposite charges. This results in enhanced softness and a more pleasant tactile experience when touching your hair.
Additionally, these surfactants improve the smoothness of the hair surface, make combing easier, and aid in detangling, all of which contribute to healthier, less breakable hair.25
A few examples are:
3. Cetrimonium Chloride 28
4. Stearamidopropyl Dimethylamine 28
Ceramides are waxy, lipid-based materials that are hydrophobic. They are naturally present in the cellular lipid bilayer of the human body.29 According to scientific research, they are effective in strengthening hair fiber and preventing hair breakage.30,31
Hydrolyzed proteins, or the amino acid molecules they contain, can bond with the hair shaft and enhance its strength. This results in improved mechanical strength for the hair fiber, as well as a smoother surface and increased shine.32
Today, there are different types of protein ingredients available, and their effectiveness is determined by the size of the protein molecules and their molecular weight.33 You can find them in products such as protein treatments, shampoos, and conditioners.
Protein fractions that are smaller in size are able to penetrate the hair fiber and reach the cortex, where they can strengthen the inner matrix.34
A few examples are:35
2. Wheat amino acids
3. Hydrolyzed keratin
4. Hydrolyzed soy protein
To maintain healthy hair and scalp, the product you use must contain a mix of humectants and moisturizing agents. This will balance the moisture levels and prevent dryness, resulting in hair that looks natural and healthy.25
Our top hydrating ingredient suggestions are:
1. Vegetal Glycerin 36
2. 1,3 Propanediol 37
3. Betaine 38
4. Zinc PCA (Pyrrolidone Carboxylic Acid)
These ingredients could either be sourced naturally (e.g. natural oils & butter) or petroleum-derived (mineral oil, petrolatum).
Natural oils and butter are preferred due to their origin, sustainability, and multifunctional benefits. Regularly using these oils can minimize hair breakage and make hair glossy, shiny, and healthy.39
A comprehensive strategy is necessary to address hair breakage. This involves taking some basic steps to improve the quality of the hair shaft.
Some fundamental steps:
● Customized Hair Care Regimen
● Keep them Hydrated and Conditioned
● Oil Therapy
● Minimize the damage
Hair breakage is a widespread problem that often leads to diminished hair quality and density, mainly due to protein loss from various factors. To mitigate this issue and take great care of your hair, steer clear of harsh combing, brushing, and aggressive chemical treatments.
A well-curated styling regimen, coupled with keeping your hair moisturized and conditioned, can go a long way in safeguarding against breakage.
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