What Are the Most Common Causes of Hair Loss at Different Ages?

Hair loss is rarely caused by a single factor. Hormonal changes, genetics, stress, lifestyle and nutrient intake can all affect the hair growth cycle. The most likely cause often depends on age and sex.

Ages 20–30

Women

Common causes of hair loss at this age include:

Stress and lifestyle factors

Ongoing stress, lack of sleep or excessive demands can disrupt the hair growth cycle. This may cause many hairs to enter the telogen, or resting, phase at the same time.

Nutrient deficiencies

Possible deficiencies at this age include iron deficiency, low zinc levels, insufficient protein intake and B vitamin deficiencies. Hair is one of the body's fastest-growing tissues and is particularly sensitive to nutrient supply.

Hormonal changes

Changing contraceptives, polycystic ovary syndrome (PCOS) or hormonal fluctuations can also trigger hair loss.

Men

Hereditary hair loss (androgenetic alopecia)

The most common cause at this age is hereditary hair loss, also known as male pattern hair loss, which involves the effects of the hormone DHT.

Typical signs include a receding hairline, thinning at the crown and progressively finer hair strands. For many men, this process can begin around the age of 20.

Ages 30–40

Women

At this age, several factors often act together.

Postpartum hair shedding

Following childbirth, hormonal changes can cause many hairs to enter the telogen phase at once. This generally begins 2–4 months after giving birth and is temporary.

Chronic stress

The combined demands of work, family and other life circumstances can affect the hair growth cycle.

Thyroid conditions

An underactive or overactive thyroid can also be a cause of hair loss.

Men

Hair loss at this age is most often a progression of hereditary hair loss. Hair strands gradually become finer, grow for shorter periods and become increasingly sparse. Thinning may become more noticeable at the crown and along the front hairline.

Ages 40–50

Women

Perimenopause

A common cause at this age is perimenopause. Hormonal changes can lead to lower oestrogen levels, a shorter hair growth phase and finer hair strands. Hair may become sparser and lose density.

Nutrient absorption issues

The absorption of certain vitamins and minerals may become less effective.

Men

Hair loss at this age is generally a more advanced stage of hereditary hair loss. Some follicles no longer produce thick hair strands, but instead produce very fine, downy hairs.

Over 50

Women

Hormonal changes after menopause

A common cause of hair loss at this age is postmenopausal hormonal change. Lower oestrogen levels can shorten the hair growth cycle and make hair strands finer. Hair loss is often diffuse, meaning that it occurs across the scalp.

Men

The main cause remains hereditary androgenetic hair loss. By this age, many men have significant thinning or balding at the crown.

Important to know

Hair loss usually develops through a combination of factors rather than a single cause. These may include:

• Hormonal changes.
• Stress.
• Nutrient deficiencies.
• Genetics.
• Scalp condition.
• Mechanical damage.

Supporting hair is therefore often most effective when several areas are addressed together:

• Adequate nutrient intake.
• Gentle haircare.
• Support for hair follicle function.
• Maintaining scalp health.