Why is my Hair Thinning?

Hair thinning may be caused by many factors, including genetics, hormonal shifts, stress, aging or nutritional issues. If you are not living with a condition like alopecia, hair thinning may also be caused by lifestyle factors or scalp conditions.

Thinning hair may also be an early warning sign of hair loss, which affects 85% of men in their lifetime and up to 55% of women (1). In this article, we will go through the most common causes of hair thinning, what hair thinning looks like in men and women and ways you may be able to treat your thinning hair.

Note that this information is general in nature and does not constitute medical advice. Individual results may vary. A consultation is required to determine suitability.

What causes hair to thin?

Thinning hair may be caused by many factors, including diet, health conditions and lifestyle. These factors may affect your hair follicles in different ways, such as:

• Androgenetic alopecia: Genetic conditions like alopecia cause hair follicles to shrink over time, which may shorten hair lifespan and cause progressively finer, shorter hairs to grow.
• Telogen effluvium: Stress or shock may cause hair follicles to prematurely enter a resting phase, which may later cause notable hair shedding and thinning (2).
• Nutritional deficiencies: If hair matrix cells are not receiving the proper nutritional support, such as iron or protein, this disrupts the function of the hair follicles and may cause hair to be brittle and thin.

Medical Director Dr Adam Cho (AHPRA No. MED0001200342)

"Genetics plays a significant role in male pattern baldness; however, there are other factors too, such as stress, health, medications and that all plays a significant role in initiating or causing the hair loss.’

What thinning hair looks like:

Thinning hair in men

In men, thinning hair typically starts as a receding hairline. Depending on the shape of your head, it may form an ‘M’ or ‘U’ shape. It may also appear as clear bald patches across the scalp or as a visible thinning of the crown (3).

You may also notice more loose hairs on your pillow, in your shower or bath, or when you run your hands through your head.

Thinning hair in women

Thinning hair in women may be more subtle than in men. It typically involves a widening parting line instead of a receding hairline, with thxinning beginning at the crown. Thinning hair may also cause more general scalp visibility in women or a noticeable change in your hair texture.

Your hair may also be thinning more if you notice an excessive amount of shedding in your brush, drain or on your shoulders.

How is thinning hair diagnosed?

Typically, thinning hair may be diagnosed by an AHPRA-registered doctor performing a physical examination of the scalp and checking your medical history. They may also perform a specialised test like a pull test, trichoscopy, or scalp biopsy to pinpoint the cause (2).

At Gro Clinics, our hair examination and restoration approach is performed by AHPRA-registered doctors and is designed for long-term results.

Reasons your hair may be thinning:

In order to reduce or treat thinning hair, it is important to identify the main cause. Potential reasons your hair could be thinning include:

Medication

Certain medications may be affecting your hair health and causing your hair to become thinner. Medications that may cause hair thinning include:

• Chemotherapy treatments
• Blood thinners
• Antidepressants and mood stabilisers
• Blood pressure medication
• Hormonal medication
• Weight loss drugs

If you suspect your medication is affecting your hair health, it is important that you do not stop taking it. First, you should consult with your health care professional so they can determine a solution. You may need to switch medications, lower your dosage or begin a different form of treatment.

Nutrition

Hair and hair follicles are non-essential body functions, so when you are lacking specific nutrients, your body may prioritise other functions and organs. This deficit may then result in less hair growth and thinner, more brittle hair.

The key nutrients you may need for hair health are:

• Iron
• Protein
• Vitamin D
• Zinc
• Biotin (vitamin B7)

If diet or health conditions are affecting your intake of these nutrients, you may notice your hair thinning. Check out our guide to the best foods to support healthy hair growth for more information.

Health conditions

Certain health conditions may disrupt the hair growth cycle, cause nutrient deficiencies, affect scalp and skin conditions or create hormonal imbalances, causing hair thinning or hair loss. Health conditions that may be affecting your hair include:

• Hormonal imbalances: Thyroid disease, polycystic ovary syndrome, pregnancy and menopause may have an effect on your general hormone levels, which may trigger hair thinning.
• Autoimmune diseases: In Alopecia areata, lupus and similar conditions, the immune system mistakenly attacks hair follicles, which may create patchy hair loss, hair thinning and scarring.
• Scalp and skin infections: Inflammatory skin conditions such as psoriasis or seborrheic dermatitis may affect the scalp and hair follicles or cause deficiencies that disrupt hair growth.
• Nutritional deficiencies: A lack of essential nutrients, either through diet or other health conditions, may be affecting the health of your hair follicles and affecting hair growth.

Lifestyle changes

Thinning hair may also be caused by consistent lifestyle factors that are affecting the quality of your hair health. If you are not getting enough sleep, you may be affecting your circulation and hormone balance, which may cause changes to your hair follicles and result in thinner hair.

Excessive alcohol consumption and smoking may be restricting your blood flow or introducing oxidative stress. This may be causing an acceleration of alopecia and damaging your hair follicles.

Stress

Living with significant stress may cause your follicles to enter a premature resting phase, which may lead to excessive shedding and thinning hair. Stress-induced hair loss typically fits into one of three categories: the previously mentioned telogen effluvium and alopecia areata, and trichotillomania, a coping mechanism where, due to stress, you may be subconsciously pulling your hair.

By learning to manage stress and practice mindfulness, you may be able to reduce hair thinning and hair loss.

Hair care routines

Some common daily hair habits may not be healthy for your hair and may be causing thinning. These include:

• Tight hairstyles/headwear: Routinely pulling your hair into tight hairstyles like high, slicked-back ponytails, buns, braids or dreadlocks may pull out the hair, resulting in damaged follicles and thinner hair regrowth.
• Washing habits: Scrubbing soaking wet hair too hard may cause you to pull out hair and damage follicles. You may also be brushing or detangling too roughly while the hair is wet, causing more hair loss.
• Heat and chemicals: Shampoos with strong sulphates or parabens may damage the hair or strip the shaft of its moisture. Daily use of flat irons, curling wands and blow dryers may also be scorching the cuticle, and frequent colouring and bleaching may be stripping the hair's protective layer.

How to treat thinning hair:

Depending on the root cause of your thinning hair, you may be able to rescue or recover your hair and encourage a healthier scalp. Here are a few treatments and choices you can make to treat thinning hair:

Diet

Certain foods are rich in the previously mentioned nutrients your hair needs to remain healthy, thick and voluminous. By monitoring your diet, you may be able to encourage natural hair growth and treat your thinning hair. Some foods to consider include:

\* Vitamin D is difficult to obtain from food alone. Safe sun exposure may be a better source.

Lifestyle changes

By practising healthier lifestyle choices, you may be able to support healthier hair and help to address the root cause of your thinning hair. These lifestyle changes include quitting smoking, creating a nutrient-rich diet, practising gentler haircare and reducing your alcohol intake.

For more gentle hair care, avoid tight hairstyles or headwear that is too tight, and avoid aggressively brushing your hair. Before using hair products, see if there are any sulphates or other harsh chemicals listed. Reducing perms and heat treatments may also help thinning hair recover.

Stress management

Using effective stress management techniques may help you avoid cortisol spikes that may affect the resting phase of your hair. These spikes may also increase hair shedding and disrupt sleep cycles.

Methods to reduce stress may typically be done at home. Consider practising mindfulness and meditation techniques for 10 to 20 minutes a day. Exercising regularly may also help reduce stress, but pushing your body too hard may increase stress and affect your nutritional intake.

Medical treatment

Depending on the underlying cause of your hair thinning, you may be able to use medical treatments and therapies to reduce your hair thinning. Treatments that may be prescribed to deal with thinning hair include:

• Medications: After a consultation, a healthcare professional may suggest topical treatment like minoxidil or other prescriptions used to treat hair loss (4). (Prescription hair care treatments are available following a consultation with a doctor to assess suitability.)
• Procedural treatments: For more advanced conditions, a medical professional may suggest low-level laser therapy, growth factor therapy, or a hair transplant procedure. (5)(6)

Disclaimer: This information is general in nature and does not constitute medical advice. Individual results may vary. A consultation is required to determine suitability.

Hair Growth at Gro Clinics

Gro Clinics offers hair restoration care in Auckland, New Zealand. A consultation is required to assess suitability.

The Gro Clinics service includes:

• A free 15-minute discovery call with a hair growth advisor.
• An in-person conversation with our team and scalp evaluation.
• AHPRA-registered practitioners.
• Structured, in-clinic training and hands-on education before performing or assisting in procedures for all medical and clinical teams.
• Flexible payment options for eligible patients.
• Post-procedure support and annual check-ins.

Hair thinning FAQs

Can thinning hair grow back?

Yes, thinning hair may be able to grow back if the root cause of the thinning can be treated. However, success may depend on how soon the condition may be treated and whether there are any hair follicles still alive and healthy.

What vitamins am I lacking if my hair is falling out?

The following vitamins and mineral deficiencies may be linked to hair shedding:

• Vitamin D: For new follicles and regulating growth.
• Biotin: For keratin production, the main protein in hair.
• Vitamin B12: For red blood cell production, which carries oxygen to the scalp.
• Iron: Supports follicle oxygen.
• Zinc: Assists in tissue repair and follicle function.

What foods should you avoid for hair loss?

For hair loss, some foods you should avoid include, but are not limited to:

• Refined sugars: Candies, pastries, sweet coffees or sugar-rich soda may increase androgens and accelerate hair shedding.
• Simple carbohydrates: White bread, white rice, and baked goods may increase excess sebum production in your system, which may cause inflammation.
• Fried or greasy food: fried chicken, fast foods and French fries have trans fats that may hinder blood circulation to the scalp.
• High-mercury fish: Swordfish, king mackerel and certain types of tuna may introduce too much mercury to your system, which may affect your protein and zinc absorption.

What not to do when hair is thinning?

If you have noticed your hair is thinning, try to avoid or manage your stress. You should also try to stick to natural, loose hairstyles and avoid excessive heat or bleach. Closely monitor your diet and focus on taking better care of your scalp health.

Which organ is linked to hair loss?

As hair is in a non-essential tissue, hair health may depend on several internal organs working together to balance hormones, nutrients and toxins. However, the two organs most commonly linked to hair loss are the thyroid gland and the liver.

The thyroid produces hormones that regulate your metabolism and control your hair growth cycle. The liver stores essential vitamins, helps process proteins and eliminates excess hormones.

Can I naturally reduce thinning hair?

Yes, depending on the cause of your thinning hair, you may be able to naturally reduce or address your thinning hair. By making positive lifestyle changes like quitting smoking, fixing your sleep schedule and dieting properly, you may be able to naturally encourage better hair health and reduce thinning hair.