Understanding Hair: Anatomy, Growth Cycles, and Factors Affecting Health

Hair is not just a fashion statement; it's a complex integration of biological components. Composed mainly of keratin, a protein also found in nails and skin, each strand has a unique genetic footprint.

A single hair consists of the cuticle, cortex, and medulla. The cuticle is the protective outer layer, the cortex holds pigment and moisture, and the medulla, the hair's innermost section, is often absent in fine hair.

Hair growth has three phases: anagen (active growth), catagen (transition), and telogen (resting). The anagen phase can last several years, while the telogen phase can result in shedding of 25 to 100 hairs daily.

Each hair follicle operates independently to ensure constant coverage. The asynchronous nature of hair growth cycles prevents all hairs from falling out simultaneously, a phenomenon that's vital for the survival of our hairy ancestors.

Growth rates and cycles are influenced by factors such as age, genetics, hormones, and nutrition. For instance, hair grows faster in summer due to increased circulation and prolonged anagen phase triggered by warmer temperatures.

Surprisingly, diet plays a crucial role in hair health. Deficiencies in iron, vitamins D and E, and zinc can lead to hair loss. A balanced diet supports the hair growth cycle and maintains hair density.

While shedding is a natural part of the hair cycle, excessive hair loss can be triggered by stress, illness, or hormonal imbalance. Understanding your hair's growth cycle can aid in identifying and treating hair health issues.