Shiny, silky smooth hair is perceived as healthy hair. But what about frizzy hair? The appearance of damaged hair can be a sign of excessive hair brushing or the overuse of chemicals and thermal treatments. It can also be a sign of internal factors, such as nutrient deficiencies, or even be a result of genetics. Split ends can be taken care of, but it is important to understand what causes them and how to prevent them.
The hair structure consists of three layers, the cuticle, cortex, and medulla:
Cuticle: Outermost layer. Composed of tiny dead overlapping cells, like roof shingles or fish scales. This transparent layer serves as a protectant for the other layers.
Cortex: Middle layer. The cortex is the main component of hair containing keratin and fatty acids that adds elasticity and resistance to the hair. The cortex also contains a pigment that gives hair its natural coloring.
Medulla: Inner core. The medulla contains more loosely packed keratins, fatty acids, and pigment. This core is only seen in thicker, coarse hairs.
Split Ends and Why They Happen
Split ends are exactly what they sound like. They occur when the hair shaft splits from a single strand to multiple, usually occurring at the tip. This is typically a sign of damaged or unhealthy hair. Split ends occur in response to excessive or repeated chemical treatments, grooming habits, and various environmental exposures. These can result in progressive damage to the hair, seen as “weathering”. This is when the hair becomes frizzy, and tangled, making it difficult to maintain. After repeated exposures, the outer protective layer of the hair, the cuticle, no longer maintains its protective function. The loss of this layer renders the rest of the hair strand more susceptible to subsequent damage and breakage, resulting in the appearance of split ends.
Anything that can damage the outermost layer of the hair shaft, the cuticle, can lead to split ends. Common causes of split ends include excess heat applied to the hair, chemicals added to the hair, and physical damage.
The use of blow dryers, straightening irons, curling irons and other various heat producing tools are common thermal treatments used to manipulate the hair. Thermal treatments are effective in temporarily changing the shape of hair or speeding up the drying process. These processes can also cause damage to the hair, leading to the appearance of split ends. When heat is directly applied to the hair with the use of irons, or indirectly by a blow dryer, it removes the presence of water retained within the hair and can damage the cuticle. The lack of hydration in the hair results in the cuticle becoming brittle and more susceptible to cracking, which results in split ends. The damage process is accelerated by continuous and extreme thermal exposures.
When the hair is wet, it can naturally stretch up to 30% without damage. However, if stretched beyond 30% it can lead to irreversible damage and hair fracture. Excessive combing when the hair is wet can lead to additional stretching, and consequently hair breakage. Brushing the hair when dry can also lead to the formation of split ends. This is a result of repeated friction on the hair shaft, which causes damage to the cuticle layer. When this layer becomes damaged, the small scale-like cells of the cuticle become frayed and lead to the formation of split ends.
Artificial hair color and chemical hair processing are common chemical processes that can lead to hair damage. The use of chemical dyes, bleaching agents, hair relaxants and perming solutions all lead to progressive damage of the hair. Perms and relaxants are used to change the shape of the hair from straight to curly, or from curly to straight. For this process to occur, the disulfide bonds that give hair its natural structure must be broken. Disulfide bonds are responsible for both the shape and strength of the hair. When these are broken, the strength of the hair is weakened. Similarly, when changing the color of the hair, the chemicals must penetrate the cortex, the middle layer. Before they reach the cortex, they must get go through the outer cuticle layer of the hair, the cuticle. This causes damage to the cuticle layer and leads to the appearance of frayed or split ends as a result.
Overexposure to ultraviolet radiation from the sun can cause both physical and chemical damage to the hair. UV radiation causes hair to lose its natural color, and become hypopigmented or lightened. This is why in the summer, hair generally turns lighter as there is more sun exposure. Ultraviolet sun damage has the same effect on protein bonds as it does pigmentation on the hair. Over time protein and keratin bonds within the hair can be damaged by repeated sun exposure. Protein is what gives hair its flexibility, strength, and shine. With both the color and protein being affected by the sun, the hair can become dry, weak, brittle, and rough in texture while losing its natural color and natural shine.
Table 1. Some Tips to Battle Split Ends
· Limit the use of thermal treatments
· Use lower heat temperatures
· Let hair air dry naturally
· Use thermal hair protectants prior to thermal use
· Apply hair oils before combing wet hair to reduce excessive stretching
· Use a wide tooth comb when combing wet hair
· Avoid over brushing or towel drying hair
· Reduce chemical exposure to hair
· Avoid “Ammonia Free” hair dye, as they contain other damaging chemicals
· Use semi or demi-permanent hair dyes to avoid ammonia exposure
· Wear protective hair garments
· Apply hair sunscreen
There is an average of 100,000 hairs on the top of the head that grow at a rate of 0.3-0.4mm a day. This process requires a lot of energy and proper nutrients. Nutrition plays a pivotal role in maintaining the health of hair. A balanced diet of protein, vitamins, and minerals are a good way to get nutrients needed for healthy hair. However, if there is nutritional imbalance or deficiency, this can lead to the progression of damaged hair. While there are many vitamins and minerals that can help supplement and maintain the integrity of hair, zinc, iron, and protein are among some of the most influential.
Table 2. Nutrients for Healthy Hair
Where to Find
Influences hair follicles and hair growth
Lack of zinc may result in decreased hair growth
Oysters, beef, turkey, chicken, cocoa, legumes, and peanuts
Important for the production of hemoglobin, which is responsible for the transport of oxygen to the body for growth and repair of cells
Hair follicle matrix cells are fast growing. Without adequate iron, the cells will not have enough nutrients to grow and divide. This can result in decreased hair growth
Meats: Beef, pork, poultry, pork, lamb liver, fish
Veggies: white beans, pistachio nuts, green parsley leaves, dried apricots and figs
Amino acids & Protein
The amino acids cysteine and methionine are precursors to keratin hair protein synthesis. Proteins, specifically keratin, are found in the cortex and serve as a structural component of the hair
Deficiency of protein may result in hair thinning, weakness, and hair loss[7,10]
Eggs, lentils, quinoa, almonds, peanuts, broccoli, edamame, avocado, tofu, cottage cheese, Greek yogurt, fish and various meat sources
In addition to external and nutritional factors that can lead to the development of split ends, there are also internal or genetic factors that can also cause split ends.
Trichorrhexis nodosa is an inherited autosomal dominant disorder of the hair shaft in which thickened or weak points (nodes) cause weakening and easy breakage of the hair. It is the most common inherited defect of the hair, but it may also be acquired in people who have normal hair that has been exposed to enough damage. This condition is also described as “bamboo hair”. Trichorrhexis nodosa leaves the hair more susceptible to damage and breakage due to the weak points along the strand of hair. Damage can be induced by common triggers, such as thermal and chemical treatments, and over brushing the hair. This condition can be identified based on the location of where the split ends occur. Since the weak nodes are dispersed along the entire hair shaft, split or frayed ends may be present in the middle of the hair shaft, as opposed to the tip.
Trichothiodystrophy is another example of an inherited condition that can cause an increased number of split ends. It is a rare autosomal recessive genetic disorder that manifests itself in many body systems and tissues. However, this disorder frequently affects the hair. Trichothiodystrophy is characterized by sulfur-deficient fragile and brittle hair. Sulfur is one of the main components responsible for maintaining the strength and integrity of the hair. When hair has an abnormally low amount of sulfur, it will not be strong enough to withstand daily trauma to the hair, such as brushing. This condition typically results in short, sparse hair.
Aside from cutting off split ends, various other solutions can help maintain and preserve hair health without compromising hair length. Popular treatments can be found in the kitchen.
Oils play an important role in protecting the hair from damage. They function by filling the gap between the overlapping cuticle cells. This serves to prevent the penetration of aggressive substance that may damage the hair. This property also helps to mask the appearance of split ends by improving the natural shine and silkiness of hair. When combing wet hair, oils also help to limit the additional stretch of the hair, and therefore reduce irreversible hair damage. There are many oils that can be used for these purposes, such as, argan oil, mineral oil, sunflower oil, avocado oil, olive oil, jojoba oil, and just about any other type of oil.
Coconut oil is the only oil that has been shown to be effective in reducing the amount of protein loss in both damaged and undamaged hair when used as a pre and post-wash grooming product. This means that coconut oil may be effective in both preventing and treating protein loss in hair, therefore reducing the risk of hair damage. All of these oils can be used as a hair mask to provide extra nutrients and protection, or as a mild leave-in treatment that also serves as a shine booster and frizz minimizer.
How to Prevent Split Ends
Identify and avoid triggers that commonly cause split ends
Avoid excessive and aggressive brushing and combing of both wet and dry hair
Limit excess applied heat to the hair
Decrease the frequency of chemically applied hair treatments
Ensure proper daily nutrient requirements
Use moisturizing oil treatments to preserve the cuticle layer
Maintain hair health by getting trims several times a year
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