What causes thinning hair?

Hair thinning occurs when hair follicles begin to produce fewer strands overall or strands that are finer in diameter³. To understand what causes thinning hair, it helps to know how hair grows in the first place.

Under normal conditions, a single strand of hair stays on your head for two to six years before resting briefly, then falling out to make way for new growth. At any given time, around 90% of your hair is in the anagen (growth) phase, with 10% at rest³. When thinning occurs, it’s often because the growth phase has shortened and more hairs have entered the telogen (resting) phase.³
Read on as we unpack various thinning hair causes.

Age and genetics

Hair thinning becomes a more common hair problem with age – but genetics play an equally significant role. Genetic sensitivity to DHT – a hormone derived from testosterone – causes follicles to gradually shrink, producing finer, shorter strands with each growth cycle⁴. As we age, this accelerates: the anagen phase naturally shortens, so hair renews at a slower pace. This is why male pattern hair thinning affects up to 80% of men and female pattern hair thinning impacts 50% of women at some point during their lifetime⁴.

Hormonal changes

Hormonal-related hair thinning is common and can occur during periods of significant hormonal change.

During pregnancy, increased oestrogen levels keep more hairs in the anagen phase for longer, making hair grow faster. After childbirth, those anagen hairs often enter the shedding phase simultaneously – which is why many women notice increased hair fall around two to four months postpartum⁶.

Hormonal shifts associated with menopause can also influence the hair growth cycle. As oestrogen levels decline, the growth phase may shorten, leading to reduced hair density and increased thinning over time².

Thyroid conditions can have a similar effect, disrupting the normal growth cycle and contributing to gradual thinning across the scalp².

Chronic stress

Significant physical or emotional stress can trigger a condition known as telogen effluvium – one of the most common causes of diffuse hair shedding. Under stress, large numbers of follicles are prematurely pushed from the growth phase into the resting phase. Those hairs then shed roughly two to four months later, which is why many people don’t immediately connect a stressful event with subsequent hair fall⁷. Because the delay can be significant, telogen effluvium is often mistaken for other thinning hair causes.

Nutritional deficiencies

Hair follicles are among the body’s most active structures, requiring a steady supply of nutrients to function. When the body is low in iron, protein, zinc, or certain vitamins, the hair growth cycle can be disrupted – leading to increased hair fall and finer regrowth. Unlike genetic hair thinning, which tends to follow a pattern around the hairline or crown, nutrient-related hair fall typically presents as diffuse thinning across the scalp⁹.

Breakage and damaging hair habits

Frequent heat styling, tight hairstyles, and rough handling can cause breakage that makes hair appear thinner. Tight hairstyles, such as slicked-back ponytails, buns, braids, or extensions, can place tension on the hairline and temples. Meanwhile heat styling, rough brushing, towel drying, and chemical treatments can all weaken the hair fibre. When you style thinning hair, these fragile strands may be more prone to snapping, reducing overall volume and density.

Female pattern hair thinning vs male pattern hair thinning

Both men and women can experience changes in hair density – but the pattern, location, and progression often look quite different. Male pattern hair thinning typically affects the hairline and crown1, while female pattern hair thinning tends to appear as a widening part and reduced density across the top of the scalp².

How to stop thinning hair: 6 hair fall prevention tips

Hair thinning isn’t always something you can “stop” completely, especially when genetics or age are involved. But the right routine can help support stronger-looking hair, minimise breakage, and create a healthier environment for growth.

Below, we explain how to reduce hair thinning with the right habits and hair care routine.

1. Use thickening, fortifying hair products

Thickening hair products help improve the appearance of thinning hair by lifting at the root and coating hair to temporarily increase the diameter of individual strands. This can make strands easier to shape when you style thinning hair and make hair appear fuller. For added support, look for hair care formulas with amino acids – the building blocks of the proteins that make up your hair – to help strengthen the hair fibre and improve its resistance to breakage.

The Dyson Amino™ leave-in scalp bubble treatment is clinically proven to reduce hair fall by 63%¹⁰. Its foam-to-serum formula delivers an amino acid blend to hydrate the scalp and strengthen strands at the root, helping thinning hair look and feel more resilient.

2. Eat a balanced diet

When it comes to hair fall prevention, what happens inside the body is just as important as the products you apply to your hair. Aim for a balanced diet that includes a mix of the below nutrients.

• Protein: eggs, chicken, fish, and legumes
• Iron: red meat, spinach, and lentils
• Zinc: pumpkin seeds, chickpeas, and beef
• Biotin: eggs, almonds, and sweet potato
• Vitamins A, C, D, and E: leafy greens, citrus, fatty fish, and nuts
• Omega fatty acids: salmon, walnuts, and flaxseed

If you struggle to get enough nutrition through diet alone, speak to a healthcare professional about supplements or other alternatives.

3. Manage stress levels

Managing stress is equally important: periods of prolonged stress can disrupt the growth phase, causing more hairs to enter the shedding phase at the same time. Supporting your overall wellbeing through regular exercise, quality sleep, and stress-management techniques can help create a better environment to maintain healthy hair growth.

4. Practise gentle hair habits to reduce breakage

If you believe your hair is thinning, focus on minimising unnecessary stress on the hair fibre. Use a wide-toothed comb to detangle wet hair, avoid tight hairstyles that place tension on the roots, and consider taking a break from chemical treatments such as bleaching, colouring, or relaxing.

Hydration can also help improve hair’s resistance to breakage. The Dyson Omega™ hydrating hair oil uses a blend of seven omega-rich oils to smooth the hair surface, reduce friction between strands to reduce frizz, protect against hair breakage, and leave an instant shine. Combined with gentle styling habits, it can help preserve the volume you already have and make thinning hair appear fuller.

5. Style hair with minimal or no heat

Protect hair from heat damage by styling with minimal to no heat where possible. Tools that use controlled airflow, rather than extreme temperatures, can help reduce unnecessary stress on fragile strands.

The Dyson Supersonic Nural™ Intelligent hair dryer is designed to help protect scalp health11 by automatically adjusting airflow temperature as the device approaches the scalp. Using a network of sensors, it helps maintain a comfortable scalp temperature while still delivering fast drying performance.

The Dyson Airwrap Co-anda 2x™ multi-styler and dryer is the ideal Dyson Airwrap™ for thin hair. Powered by the Dyson Hyperdymium™ 2 motor, it uses powerful, controlled airflow to curl, smooth, dry, and shape hair, while adapting heat to your preferred styling settings for each attachment. This helps create volume and movement with less reliance on excessive heat.

6. Consult a medical professional

While good hair care habits can support hair fall prevention, they can’t address every cause of hair thinning. If you notice sudden shedding, rapid thinning, or changes that don't improve over time, consider speaking with a dermatologist or healthcare professional. They can help identify underlying factors and recommend the appropriate next steps for your situation.

Now that you know how to stop thinning hair with the right hair fall prevention strategies, take a closer look at Dyson’s styling technology and discover the difference between the Dyson Airstrait™ straightener and the Dyson Airwrap™ multi-styler and dryer to prevent unnecessary damage to hair.

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