HAIR RESTORATION
What Causes Hair Loss?
Common causes of hair loss, why the same visible change can arise from different patterns, and when assessment helps.
Hair loss is a symptom rather than a single diagnosis. The same visible change — more hair in the shower, a widening parting, a receding hairline, or patches of thinning — can arise from several different underlying patterns. Some patients have a gradual inherited pattern of thinning (androgenetic alopecia). Others experience sudden diffuse shedding after illness, major stress, rapid weight change, pregnancy, or medication change. Some have a nutritional deficiency, thyroid disorder, or hormonal shift that needs identifying before any treatment plan makes sense.
Understanding the likely cause is the most important step — because different patterns respond to different approaches, and some respond best when addressed early.
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Pattern hair loss (androgenetic alopecia)
This is the most common cause of progressive hair thinning in both men and women. In men, it typically presents as recession at the temples and thinning at the crown — the familiar male pattern. In women, it usually presents as diffuse thinning across the top of the scalp with a widening parting, often without recession. Pattern hair loss is genetically influenced and mediated by the effect of dihydrotestosterone (DHT) on hair follicles. It is progressive, which means earlier treatment generally preserves more hair than waiting.
Stress-related shedding (telogen effluvium)
Telogen effluvium is a common cause of sudden diffuse hair shedding that typically follows a trigger by 2–3 months. Common triggers include major physical illness, surgery, severe emotional stress, significant weight loss, crash dieting, childbirth, and stopping hormonal contraception. The shedding can be alarming — patients often describe handfuls of hair — but the condition is usually self-limiting. Most patients see improvement within 6–12 months once the trigger has resolved. If the shedding persists beyond this timeframe, further investigation is warranted.
Hormonal factors
Hormonal and thyroid-related causes
Hormonal changes can affect hair growth at several stages of life. Perimenopause and menopause can cause diffuse thinning as oestrogen levels decline. Thyroid dysfunction — both hypothyroidism and hyperthyroidism — can produce noticeable hair thinning or textural change.
PCOS can cause hair thinning on the scalp alongside excess hair growth elsewhere. In men, the relationship between testosterone, DHT and hair loss is well established. Where a hormonal contribution is suspected, blood tests may help clarify the picture.
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Common misconceptions
Patients frequently ask whether washing hair too often, using the wrong shampoo, or wearing hats contributes to hair loss. In most cases, these are not significant factors. Hair loss is driven by genetics, hormonal influence, health changes, or nutritional deficiency — not by routine grooming. Traction alopecia from persistently tight hairstyles is a recognised exception, but ordinary washing and styling do not cause thinning.
The more clinically relevant questions are: when did the change begin, what pattern does it follow, have there been recent illnesses or hormonal shifts, and is there reason to suspect a correctable underlying cause?
When to seek assessment
Assessment is worthwhile when hair loss is progressing, when the pattern does not fit a clear trigger, when shedding has not resolved after 6 months, when it is accompanied by other symptoms (fatigue, weight change, hormonal disruption), or when you simply want a clinical opinion on what is most likely and what your options are. At Basuto, hair restoration consultations assess the pattern, review potential causes, arrange blood tests where appropriate, and discuss treatment options including PRF, prescription medication, monitoring, or onward referral. Book an appointment.
If your main concern is current thinning or shedding, the right starting point is hair restoration. If the concern sits alongside fatigue or thyroid symptoms, blood tests may form part of the pathway. Women with hormonal symptoms may also need menopause and HRT.
Nutritional factors
Nutritional deficiency and medication effects
Iron deficiency is one of the most commonly identified nutritional contributors to hair loss — and ferritin (iron storage) can be low enough to affect hair even when haemoglobin appears normal. Vitamin D, B12 and zinc deficiency have also been associated with hair thinning.
Certain medications — including some antidepressants, anticoagulants, retinoids, beta-blockers and chemotherapy agents — can cause hair loss as a side effect. A thorough blood test review can help identify treatable deficiencies.
Frequently asked questions
Can stress cause permanent hair loss?
Stress-related shedding — telogen effluvium — is usually temporary. Most patients recover within 6–12 months once the trigger resolves. However, prolonged stress can sometimes unmask an underlying pattern hair loss that was already progressing slowly. If shedding has not improved after several months, assessment can help determine whether another factor is contributing.
Should I get blood tests for hair loss?
Not always. Male pattern hair loss is typically diagnosed from the clinical pattern alone. But if hair loss is diffuse, sudden, or accompanied by fatigue, weight change, or hormonal symptoms, blood tests can identify correctable contributors such as iron deficiency, thyroid dysfunction, or vitamin deficiency. A consultation determines whether testing is appropriate for your situation.
Is hair loss hereditary?
Pattern hair loss has a strong genetic component and can be inherited from either parent. It tends to follow a recognisable distribution — temple recession and crown thinning in men, diffuse thinning across the top of the scalp in women. However, genetics is only one factor. Hormonal changes, nutritional deficiency, thyroid dysfunction, and other triggers can cause or contribute to hair loss regardless of family history.
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