The human hair growth journey is a fascinating biological process that begins at birth. When a newborn enters the world, she already possess an impressive 5 million hair follicles, with approximately 1 million of these located on the scalp. More than just a simple strand, hair is a complex protein filament that emerges from these specialized follicles through an intricate cellular transformation. The hair formation process is remarkable. Cells in the hair bulb multiply and are gradually pushed upward, away from their nutrient source. As these cells move, they undergo a critical transformation: they die and become keratinized, creating the familiar hair structure we see and touch. Genetics play a profound role in determining our hair’s unique characteristics. The color of our hair is a result of melanin, the pigment produced by melanocytes in our skin. Two specific compounds are responsible for the diverse hair colors we observe. Eumelanin creates the spectrum from blond to black, while pheomelanin introduces the vibrant red tones. As we age and melanin production changes, hair loses its pigment, leading to the characteristic grey or white hair that comes with time.

PARTS OF HAIRS

1. HAIR ROOT – contains hair color, melanin, and stem cells for hair growth, which are essential for maintaining the natural pigmentation of hair and supporting the health of hair follicles, thereby promoting stronger and more resilient hair strands over time.
2. HAIR SHAFT – hair is a keratinous filament growing out of the epidermis. It is primarily made of dead keratinized cells. Strands of hair originate in an epidermal penetration of the dermis called the hair follicle. Hair follicles grow at the hypodermic level, and the connection between the hair follicle and the blood vessel is called DERMAL PAPILLA (hair root), a cluster of cells or bulb. The hair is formed by the multiplication of cells in the bulb. The root of the hair, which provides all the essential nutrients, gets them from the dermal papilla, and this process is crucial for healthy hair growth. Without the dermal papilla, the hair would not receive the necessary support to thrive and would ultimately become weak and fall out.

Phases of hair growth

1. Anagen Phase – This phase lasts around 4 to 6 years. During this time, 80 to 95% of the hair on the body is in the anagen phase. Hair cells at the base of the hair follicle divide repeatedly, promoting steady hair growth. The duration of this phase can range from several months to several years on the scalp. Hair grows approximately 1 cm per month, meaning it can potentially grow up to 36 inches in a lifetime. The anagen phase is the active growth period, during which the hair follicle takes on an onion-like shape and works actively to produce hair fibers. The anagen phase is further divided into the proanagen and metanagen stages, during which specific biochemical activities and cellular changes support the overall health and vitality of the hair. These sub-phases are crucial in maintaining hair strength and resilience until the follicle transitions to the next phase of the hair growth cycle. The hair root goes to the growth phase when influenced by signals from the dermal papilla.
2. CATAGEN PHASE – up to 6 years completion enters into the catagen phase, where the hair follicle is connecting to the dermal papule, which contains blood vessels that will subsequently disconnect. During this time, the hair remains in this state for up to 3 weeks. Notably, only about 1% of hair remains in the catagen phase at any point in an individual’s life. This is recognized as a transition phase (often referred to as the hair fall stage), where the hair stops growing completely and becomes detached from the base of the follicle. The hair bulb begins to break down during this period, resulting in the follicle becoming significantly shorter. This phase is also commonly known as the transition phase, marking a critical point in the hair growth cycle, and serves as a preparatory stage for the eventual shedding of hair in the subsequent phase. It is a crucial aspect of hair development and overall health, reflecting changes that are natural yet significant in the lifecycle of hair.
3. Telogen phase – also known as the resting phase of the hair growth cycle. During this critical phase, the blood supply to the hair follicles diminishes significantly, causing the hair to enter a state of dormancy. The hair follicle becomes inactive, which leads to the shedding of the hair strand, and there is often a white bulb of keratin visible at the end of the hair. This phase typically lasts for several weeks to months, allowing the scalp to prepare for new hair growth as the cycle continues. Also known as telogen effluvium. Last phase telogen – resting phase. when the hair sheds from normal to faster is known as telogen effluvium.

At root (club hair), the bulb of keratin keeps the hair in follicle unit it sheds which then starts the hair growth cycle over again. The mechanism responsible for replication of cells at base of hair and the subsequent hair growth are inactive for several months. By the end of telogen phase, the hair is only loosely attached to the follicle and can be easily pulled out simply by brushing or washing the hair. During the lifespan of an individual, hair cycles repeats around 25 times.

HAIR LOSS AND HAIR FALL

Hair loss and hair fall occur due to an imbalance in the hair growth cycle. The main cause of hair loss is the imbalance of hormones in our body.

HAIR LOSS Androgen – a male hormone in the body derived from testosterone – plays a crucial role in various bodily functions. The enzyme 5 alpha reductase converts testosterone into DHT (dihydrotestosterone), a more potent androgen. This is a main/primary reason for hair loss, influencing both the patterns and severity experienced by individuals. DHT shrinks the hair follicle, compromises the anagen phase (which is the active growth phase of hair) and shrinks the root level, effectively limiting the size and health of the follicles. These factors significantly affect the new hair growth formation, leading to thinner or weaker strands. When the hair stops growing, hair loss takes place, becoming noticeable over time. HAIR LOSS IS ANDROGENETIC ALOPECIA because it is directly related to a hormone called androgen, impacting a significant portion of the population and having various psychological and social implications.

Understanding Hair Health: The Role of Nutrition and Environment

Long-Term Illness and Nutritional Deficiencies

Long-term illnesses can significantly impact overall health, including hair health. Among the various nutritional deficiencies that can affect females, iron and zinc play crucial roles. Both minerals are essential for numerous bodily functions, and a deficiency can lead to noticeable effects, such as hair thinning or loss.

Importance of Keratin and Cysteine

Hair is predominantly composed of a protein called keratin, which is critical for maintaining its structure and strength. The formation of cysteine, an amino acid integral to keratin production, is influenced by adequate zinc levels in the body. When the body lacks sufficient zinc, the production of cysteine can be hampered, thus affecting keratin formation. This can lead to a range of hair issues that are often distressing for those affected.

Effects of Keratin Deficiency

A lack of keratin in the hair can manifest in several detrimental ways. Common symptoms include dullness, a lack of strength, dryness, and brittleness. Over time, these conditions can lead to more severe issues such as excessive shedding and breakage. This cycle can create a frustrating experience for individuals struggling with hair health, and addressing the underlying nutrient deficiencies is pivotal for improvement.

The Impact of Diet

Diet plays a vital role in hair health. Insufficient protein intake can lead to hair fall as the body requires adequate protein to sustain hair growth and repair. Conversely, an excessive diet, particularly those high in certain fats and sugars, may also contribute to hair loss. Striking a balance with a nutrient-rich diet that includes adequate protein is essential for maintaining vibrant and healthy hair.

Water Quality and Hair Health

Additionally, the quality of water consumed cannot be overlooked, as heavy metals and pollutants found in water sources can exacerbate hair loss issues. Filtering water or ensuring access to clean, fresh water can be beneficial to maintaining overall health, including the health of your hair.

Environmental Factors

Weather changes, especially during winter months when the air tends to be drier, can also lead to hair fall. Cold weather can strip moisture from the hair, making it more vulnerable to damage. Protective measures like wearing hats or using hydrating hair products can help combat the harsh effects of winter.

In conclusion, maintaining healthy hair requires awareness of both nutritional intake and environmental factors. By understanding these components, individuals can take proactive steps to support their hair health and overall well-being.

Stress – accelerates hair growth cycle, which may seem counterintuitive, as stress is often associated with negative health effects. When the body is under stress, it releases various hormones that can impact hair follicles, causing them to enter the growth phase more quickly than usual. This can lead to an initial increase in hair growth, but over time, chronic stress can cause hair thinning and loss, highlighting a complex relationship between stress and hair health. Understanding this cycle is crucial for managing stress effectively and maintaining healthy hair.