Hair thinning at age 40: normal or a sign of trouble?

Entering their 40s, many women begin to notice changes in their hair. Hair that was once thick and glossy gradually feels thinner, more prone to shedding, and may appear less voluminous when tied.

These changes often cause concern. However, experts emphasise that hair thinning in the 40s is part of the natural ageing process.

Nevertheless, there are a number of other factors that can worsen the condition and should be watched.

‘In women, as menopause approaches there is a decline in oestrogen and progesterone, hormones important for maintaining hair growth,’ they said, as reported by Byrdie on Wednesday (4 March 2026).

They explained that these hormonal changes can make hair finer and less dense.

Additionally, the hair growth cycle slows down. The resting phase of the hair follicle becomes longer, while the growth phase shortens.

This natural process, combined with genetic factors, makes hair thinning a common condition in the 40s.

Bassiri-Tehrani explained that hormonal changes related to perimenopause and menopause can cause significant disruption to the hair cycle.

‘Telogen effluvium, a condition in which many hair follicles enter the resting phase at the same time, can be triggered by physical or emotional stress, resulting in noticeable shedding,’ they noted.

Not only that, several medical conditions such as autoimmune disorders, polycystic ovary syndrome (PCOS), and the side effects of certain medications can also contribute to hair loss.

Therefore, a medical examination is necessary if the shedding feels abnormal or lasts a long time.