Roughly half of all adults experience some degree of hair thinning during their lifetime.
Noticing more hair on your pillow or a wider part line is common, but the cause isn’t always obvious. Hair loss has a long list of possible triggers, and the right response depends on which one is driving it.
This article covers the most common causes of hair loss, how to tell them apart, and when it makes sense to have your situation assessed by a practitioner.
Want to skip ahead? Book a clinical consultation at StranDr in Adelaide to have your hair loss assessed.
How the Hair Growth Cycle Works
Every hair follicle cycles through three phases. Anagen is active growth, lasting two to seven years. Catagen is a brief transition period of about two weeks. Telogen is the resting phase, lasting a few months before the hair sheds and a new one begins growing.
At any point, around 85 to 90 per cent of your hair is in the growth phase. Losing 50 to 100 hairs a day falls within the normal range.
| Phase | Duration | What happens |
|---|---|---|
| Anagen (growth) | 2-7 years | Hair actively grows from the follicle |
| Catagen (transition) | ~2 weeks | Growth slows, follicle shrinks |
| Telogen (rest) | 2-4 months | Hair rests, then sheds to make way for new growth |
Hair loss occurs when something disrupts this cycle. The disruption might shorten the growth phase, push too many hairs into rest at once, or damage the follicle so it stops producing hair altogether.
Genetic Hair Loss
Androgenetic alopecia is the most common cause of hair loss. According to the Better Health Channel, it affects roughly 50 per cent of men over 50 and around 40 per cent of women by menopause.
In men, it typically starts with a receding hairline or thinning at the crown. Women tend to notice a gradually widening part or overall thinning across the top of the scalp, usually without the hairline pulling back.
- Cause: Hormones called androgens cause genetically sensitive follicles to shrink over time
- Pattern: Predictable and progressive. Each growth cycle produces thinner, shorter hair
- Runs in families, though it can skip generations
- Treatable: Responds to early intervention. The follicles that are miniaturised but still active are easier to work with
Because this type follows a recognisable pattern, it’s also the most studied. A clinical assessment can confirm whether genetic hair loss is what you’re dealing with.
Hormonal and Medical Causes of Hair Loss
Any significant hormonal shift can trigger hair shedding. This goes beyond the genetic sensitivity described above.
- Thyroid conditions (both overactive and underactive) can cause diffuse thinning across the scalp
- Pregnancy and postpartum changes often trigger temporary shedding, usually peaking three to four months after delivery
- Menopause brings hormonal shifts that can accelerate thinning patterns
- Polycystic ovary syndrome (PCOS) may cause scalp thinning alongside excess hair growth elsewhere
Autoimmune conditions like alopecia areata cause the immune system to attack hair follicles, resulting in patchy, sometimes sudden hair loss. Scalp infections, iron deficiency anaemia, and chronic illness can also disrupt the growth cycle.
Some medications list hair loss as a side effect, including certain blood pressure medications and treatments for arthritis. If you suspect a medication is involved, speak with your prescribing doctor before making any changes.
Stress and Telogen Effluvium
A major physical or emotional stressor can push a large number of hairs into the resting phase at once. This is called telogen effluvium, and it’s one of the most common causes of sudden, diffuse shedding.
The shedding usually starts two to three months after the triggering event, which makes it hard to connect cause and effect. Common triggers include:
- Major surgery or serious illness
- Rapid weight loss or restrictive dieting
- High fever or infection
- Significant emotional stress
Telogen effluvium is almost always temporary. Once the trigger is resolved, hair typically returns to normal growth within six to twelve months. If shedding continues beyond that window, it may point to an underlying condition worth investigating.
Nutritional Deficiencies and Hair Loss
Hair needs a steady supply of nutrients to grow. When your body is running short, hair is one of the first things it deprioritises. It’s not essential for survival, so it loses out to more important functions.
| Nutrient | Role in hair health | Common in |
|---|---|---|
| Iron | Supports follicle oxygen supply. One of the most common deficiency-related causes | Women, plant-based diets |
| Zinc | Supports follicle structure. Deficiency causes diffuse shedding | Restrictive diets |
| Protein | Building block of hair (keratin). Low intake causes brittle, thin hair | Very low-calorie diets |
| Vitamin D | Plays a role in follicle cycling. Low levels linked to increased shedding | Limited sun exposure |
| B vitamins | Support keratin production | General poor diet |
Most people with a reasonably balanced diet get enough of these nutrients. Iron is the exception worth checking with a blood test if you’re experiencing unexplained shedding, particularly if you menstruate or follow a plant-based diet.
Why Hair Loss in Women Is Often Overlooked
Hair loss is often framed as something that happens to men. In reality, it’s just as common in women, but the pattern is different. Women rarely experience the classic receding hairline. Thinning tends to be more diffuse and spread across the top of the scalp.
According to Healthdirect Australia, female pattern hair loss affects around one in three women at some point. It becomes more common after menopause.
- Hormonal changes (pregnancy, menopause, contraceptive changes) are common triggers
- Iron deficiency affects women disproportionately
- Traction alopecia from tight hairstyles, extensions, or chemical treatments is another cause more common in women
- Hair loss in women can sometimes signal an underlying hormonal or medical condition
If shedding is sudden, patchy, or accompanied by other symptoms, a medical assessment is a good starting point.
When to Seek a Clinical Assessment
Not every bit of shedding warrants a clinic visit. But there are clear signals that it’s worth getting a professional opinion.
- Hair loss has been progressive over several months
- You can see your scalp through areas that used to be thick
- You’re finding large clumps of hair on your pillow or in the shower
- Your hairline has visibly receded
- Patchy bald spots have appeared suddenly
Most forms of progressive hair loss respond better to early intervention. The follicles that are miniaturised but still active are easier to work with than follicles that have shut down completely.
A clinical assessment typically involves examining the scalp, reviewing medical history, and sometimes blood tests to rule out underlying conditions. From there, a practitioner can give you a clear picture of what’s happening and what your options are.
Treatment Options for Hair Loss
Treatment depends entirely on the cause. There’s no single answer, which is why a proper assessment matters.
Non-surgical approaches
Over-the-counter topical treatments can slow the progression of genetic hair loss and, in some cases, encourage regrowth. Prescription oral medications work by targeting the hormonal component. Both require ongoing use to maintain results.
Platelet-rich plasma (PRP) therapy is a non-surgical option that may help stimulate follicle activity in suitable candidates. Results vary between individuals.
Surgical hair restoration
For hair loss that has progressed beyond what non-surgical treatments can address, FUE hair transplantation is one of the most established options. It involves relocating individual follicles from areas resistant to thinning to areas where hair has been lost.
Modern FUE techniques can produce results that appear highly natural, with minimal visible scarring. Factors like the extent of hair loss, donor hair availability, and overall health all influence whether someone is a suitable candidate for a hair transplant in Adelaide.
Any hair restoration procedure carries risks, including infection, scarring, and the possibility that results may not meet expectations. A thorough consultation is necessary to assess suitability and discuss realistic outcomes.
If you’re noticing changes in your hair, a clinical assessment is the best place to start. Dr Rahma Targett (FRACGP, AHPRA-registered, ISHRS member) and the team at StranDr in Adelaide can assess your hair loss, identify the likely cause, and walk you through the options that may suit your situation.
Contact StranDr to book a consultation and discuss your hair restoration options.