If you've noticed more hair on your pillow, in the shower drain, or in your hairbrush lately — you're not alone. Hair thinning affects an estimated 8 million women and 6.5 million men in the UK, yet it remains one of the most misunderstood and undertreated concerns in everyday health.
The good news? In most cases, hair thinning is not permanent. When you identify the root cause and address it with the right nutrition and care, hair can and does recover. Here, we break down the five most common causes of hair thinning — and what you can do about each one.
The 5 Most Common Causes of Hair Thinning
Stress & Cortisol Overload
Stress is one of the most common — and most overlooked — triggers of hair thinning. When your body is under chronic stress, it produces elevated levels of cortisol, which can disrupt the natural hair growth cycle and push hair follicles into a resting (telogen) phase prematurely.
This results in a condition called telogen effluvium, where large amounts of hair shed simultaneously — often 2–4 months after a stressful event. Many people notice the hair loss and assume something is wrong with their hair, not realising it's a delayed response to a stressful period weeks earlier.
Signs it might be stress-related: sudden increased shedding, hair coming out in clumps, thinning across the whole scalp rather than one specific area.
✦ Glowwa HAIR FOOD™ contains B vitamins and MSM that help support the body's stress response and encourage the hair cycle back to its growth phase.Nutritional Deficiencies
Your hair is one of the last places your body sends nutrients — it prioritises vital organs first. So if your diet is lacking in key vitamins and minerals, your hair is often the first place you'll notice it.
The most common deficiencies linked to hair thinning include:
- Biotin (B7) — essential for keratin production, the protein hair is made from
- Vitamin B12 — supports red blood cell production which carries oxygen to hair follicles
- Zinc — helps repair hair tissue and keeps oil glands around follicles working
- Iron — low iron (especially in women) is one of the most common causes of diffuse thinning
- Folate — supports cell division and new hair growth
Hormonal Changes
Hormones play a significant role in the health and density of your hair throughout your lifetime. Fluctuations in oestrogen, progesterone and thyroid hormones can all trigger increased shedding and thinning.
The most common hormonal triggers include:
- Perimenopause & menopause — falling oestrogen levels are one of the leading causes of hair thinning in women over 40
- Postpartum hair loss — after childbirth, oestrogen drops sharply causing widespread shedding typically between 2–5 months post-birth
- Thyroid imbalance — both overactive and underactive thyroid can cause significant hair loss
- PCOS — polycystic ovary syndrome causes androgen excess which can thin hair at the temples and crown
DHT Sensitivity (Androgenetic Alopecia)
Dihydrotestosterone (DHT) is a byproduct of testosterone, present in both men and women. In people who are genetically sensitive to DHT, it can bind to hair follicle receptors and gradually miniaturise them — causing the hair to grow back finer and shorter until it stops growing altogether.
This is the most common form of hair loss in men (male pattern baldness) but also affects many women, typically presenting as thinning at the crown and widening parting rather than a receding hairline.
DHT-related thinning tends to be progressive if left untreated, which is why early intervention with targeted nutrition is so important.
✦ Glowwa HAIR FOOD | MENS™ is specifically designed to target DHT sensitivity with ingredients that help support the male hormone pathway and nourish affected follicles.Inflammation & Scalp Health
Chronic low-grade inflammation — often driven by diet, gut health, environmental factors or skin conditions — can affect the scalp environment and impair hair follicle function. A healthy scalp is the foundation of healthy hair.
Signs of scalp inflammation include: persistent itching or flaking, sensitivity, redness or a feeling of tightness. Conditions like seborrheic dermatitis, psoriasis and eczema of the scalp can all contribute to increased shedding.
Gut health also plays a role — an imbalanced gut microbiome can impair nutrient absorption, meaning even a good diet may not be delivering what your hair needs.
✦ MSM (methylsulfonylmethane), one of the key ingredients in Glowwa Hair Food, has natural anti-inflammatory properties and supports collagen production for a healthier scalp environment.How to Tell Which Cause Applies to You
In many cases, hair thinning is caused by a combination of factors rather than a single cause. A useful starting point is to ask yourself:
- Has anything changed in the last 3–6 months? (new stress, illness, diet change, medication, life event)
- Is the thinning all over, or concentrated in one area?
- Do other family members have similar hair loss patterns?
- Have you had any recent blood tests? Low iron, B12, zinc or thyroid function are easy to check.
If you're concerned, always speak to your GP first to rule out any underlying medical causes. Once these are addressed, a high-quality hair supplement like Glowwa can help support recovery and long-term hair health.
💡 Key takeaway: Hair thinning is rarely caused by just one thing — it's usually a combination of stress, nutrition, hormones, DHT sensitivity and inflammation. Glowwa Hair Food is specifically formulated to target all five root causes simultaneously, making it one of the most comprehensive hair supplements available in the UK.
How Long Does It Take to See Results?
Hair grows approximately 1–1.5cm per month, and the hair growth cycle typically runs over 3–6 months. This means that supplement results are not instant — but they are real and measurable. Here's what most Glowwa customers report:
- Weeks 2–4: Ingredients begin to build in the system. Some customers notice improved energy and less scalp sensitivity.
- Weeks 4–6: Reduction in daily shedding — noticeably less hair in the brush and shower.
- Month 3: Visible improvements in hair density, shine and texture. New baby hairs beginning to appear.
- Month 6: Full transformation results — significantly fuller, thicker, stronger hair for the majority of customers.
In Glowwa's consumer trials: 96% of participants experienced less hair loss, 96% said their hair felt fuller, and 98% reported better overall scalp condition after a full course.
Which Glowwa Product Is Right for You?
Choosing the right Glowwa supplement depends on your specific hair concerns:
- HAIR FOOD™ — general thinning, stress, nutritional deficiency, suitable for all women
- HAIR FOOD | MENO™ — perimenopausal or menopausal hair loss, hormonal changes, fatigue
- HAIR FOOD | MENS™ — male pattern thinning, DHT sensitivity, receding hairline
- COLLAGEN CREAMER™ — add-on support for hair, skin and digestive health
Still unsure? Contact us or visit us in our Falkland, Fife salon and we'll help you choose the right product for your hair concerns.
Ready to Address Your Hair Thinning?
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