Noticing more hair in the brush or a wider parting can be unsettling. The good news is that hair thinning is very common, and in many cases there is a straightforward explanation. This guide covers the usual causes and explains when it is a good idea to get advice from a health professional.
This article is general information only and is not medical advice. If you are worried about hair loss, speak to your GP or pharmacist.
Is it normal to lose hair?
Yes. Most people shed some hair every day as part of the natural growth cycle. Noticeable thinning, patches, or a sudden increase in shedding is what tends to prompt concern.
Common causes of hair thinning
Genetics and age
The most common cause of gradual thinning in both men and women is a genetic pattern, often called pattern hair loss. In men it often shows as a receding hairline or thinning crown. In women it tends to show as a wider parting and overall reduced density.
Hormonal changes
Pregnancy, childbirth, the menopause and thyroid conditions can all affect hair. Shedding after having a baby is very common and often settles over time.
Stress, illness and major life events
A period of intense stress, serious illness, surgery or sudden weight loss can trigger a temporary increase in shedding a few months later. In many people the hair gradually recovers.
Nutrition
Low iron, low vitamin D, or a diet that is very restrictive can affect hair. If you suspect a deficiency, ask your GP about a blood test rather than starting supplements by yourself.
Medication and medical treatment
Some medicines and treatments, including some used for cancer, blood pressure and depression, can cause hair thinning as a side effect. Never stop a prescribed medicine without speaking to your doctor first.
Hairstyles and styling habits
Constant tight styles such as tight ponytails, braids or extensions can pull on the hair and lead to thinning along the hairline. Frequent heat styling and harsh chemical treatments can also cause breakage.
Scalp and skin conditions
Conditions such as dandruff, psoriasis or fungal infections can affect the scalp and sometimes the hair above it.
Autoimmune conditions
Some people develop sudden, round patches of hair loss. This can be a sign of an autoimmune condition and is worth having checked by a doctor.
When to see your GP
It is sensible to book an appointment if you notice:
- Sudden or rapid hair loss
- Hair coming out in patches
- An itchy, painful, red or scaly scalp
- Hair loss alongside other symptoms such as tiredness, weight changes or skin changes
- Hair thinning at a young age, or hair loss that is causing you distress
Your GP can look for underlying causes and talk through your options.
What can you do in the meantime?
- Handle your hair gently, and avoid very tight styles.
- Eat a balanced diet.
- Look after your scalp with a gentle routine.
- If thinning bothers you, cosmetic options such as hair fibres and styling can help you feel more confident while you find out more.
The bottom line
Thinning hair has many possible causes, and most are common and manageable. Getting advice early can give you peace of mind and help you decide on the best next step.