Increased hair shedding at certain times of the year, typically in late summer and early autumn, is a common experience. This phenomenon, known as seasonal telogen effluvium, involves a temporary increase in the number of hairs lost daily. While the sight of extra strands can cause distress, this occurrence is usually benign and part of a natural biological adjustment. Understanding the temporary nature of this shedding and the underlying hair cycle helps manage what can feel like a sudden change in hair density.
The Temporary Nature of Seasonal Shedding
The hair lost due to seasonal shedding will grow back. Seasonal shedding is a self-limiting condition, meaning the hair follicles remain viable and are not permanently damaged. Recovery begins naturally once the shedding phase concludes.
Shedding typically peaks for about six to twelve weeks, which differentiates it from chronic hair loss. Visible regrowth generally begins within three to six months after the increased shedding subsides. New healthy hairs emerge from the follicles to replace the lost strands, gradually restoring density.
The Hair Cycle and Seasonal Triggers
Seasonal hair loss results from a disruption in the natural hair growth cycle, which consists of three phases: anagen (growth), catagen (transitional), and telogen (resting). The hair is shed during the exogen phase following telogen. Normally, 85% to 90% of hairs are in the active anagen phase, with 10% to 15% in the resting telogen phase.
Seasonal changes, particularly intense sunlight exposure and temperature shifts during the summer, can trigger a higher percentage of hairs to prematurely enter the telogen phase. This synchronization acts as a biological protection mechanism, possibly a remnant of an evolutionary need to have thicker hair in colder months. Since the telogen phase lasts about three to four months before shedding, the increased number of resting hairs in summer leads to a noticeable surge in hair fall a few months later, usually peaking around September to November. This delayed shedding explains why hair loss often occurs in the fall, following summer’s environmental changes. The shedding of the old hair makes way for a new hair to begin growing in the follicle.
Supporting Healthy Regrowth and Recovery
While the hair will regrow on its own, supporting the body with targeted nutrition can optimize the recovery timeline. Hair follicles are sensitive to nutrient deficiencies because they are among the fastest-dividing cells in the body. Ensuring adequate protein intake is important, as hair is primarily composed of keratin. Specific micronutrients also support hair function and structure.
Nutritional Support
Iron is necessary for hair growth, and low iron stores (ferritin) are a common factor in non-seasonal telogen effluvium. Iron-rich foods like lean meats and leafy greens are important. Zinc is a mineral involved in hair tissue growth and repair, and B vitamins, particularly biotin, support the hair strand’s infrastructure.
Scalp Care and Stress Management
Scalp health impacts the follicle’s ability to regrow efficiently. Gentle scalp massage can improve blood circulation to the hair follicles, delivering oxygen and nutrients. Avoiding harsh styling practices, such as tight ponytails or excessive heat, minimizes mechanical stress on newly emerging and vulnerable strands. Managing stress through techniques like mindfulness or regular exercise is also beneficial, as chronic stress can prolong the telogen phase and delay a normal growth cycle.
Differentiating Seasonal Loss from Chronic Hair Loss
It is important to distinguish seasonal shedding from chronic forms of hair loss. Seasonal telogen effluvium is characterized by a temporary, diffuse increase in shedding across the entire scalp without noticeable patches or a receding hairline. The increased shedding phase lasts no more than three months before normalizing.
If shedding persists for longer than three to four months, or if the loss is accompanied by specific patterns, a medical evaluation is warranted. Chronic conditions, such as androgenetic alopecia (pattern baldness) or chronic telogen effluvium, often involve progressive thinning or specific patterns of loss, like a widening part or a receding hairline. Diffuse hair loss that continues for more than six months may indicate an underlying health issue, such as a thyroid disorder, autoimmune condition, or severe nutritional deficiency. Consulting a dermatologist or a primary care physician can help ensure a precise diagnosis and appropriate treatment plan.