What Causes Hair Loss

What causes hair loss? Hair loss comes in many different forms from overall thinning (telogen effluvium) to female pattern baldness (androgenetic), bald patches (alopecia areata) and even complete hair loss (alopecia universalis). 

Hair is such an integral part of our identity and it can be a shock to start losing it. I still remember the time I found a large bald patch on the side of my head. It was a red angry patch that itched and burned. I started to hyperventilate and cried. It really felt like I was in a nightmare.  After a year I had lost 70% of my hair and was wearing a wig and avoided certain activities like swimming or going to the gym. So what caused my hair loss? 

Types of Hair Loss

It’s worthwhile to first explain the differences between some of the more common types of hair loss and then dig into some of the causes. 

Overall Thinning (Telogen Effluvium)

Telogen Effluvium is when a large number of hair follicles go into a resting stage but the next growth stage doesn’t begin. This results in an overall thinning of the hair especially around the hairline and temples.

Female Pattern Baldness (Adrogenetic)

This is thought to be related to genetics and can start as early as puberty and usually just leads to overall thinning of hair, not a receding hairline as is the case with male pattern baldness. This form of hair loss affects an estimated 50 million men and 30 million women in the United States. [1]

Alopecia Areata and Universalis 

This form of hair loss is an autoimmune condition. The body appears to be attacking hair follicles which causes hair to fall out in patches or all over the scalp. This can also affect eyebrows, eyelashes and body hair. 

So What Causes Hair Loss?Causes Hair Loss


If you have thinning hair, this is the first place to look. Stress such as trauma, emotional stress, surgery, sleep deprivation and pregnancy can cause hair loss. These stressors can also trigger autoimmune conditions including, but not limited to, alopecia areata and universalis. In fact at the time that I found the bald patch on my scalp, I was under a significant amount of chronic stress from work. 

Hormone Imbalances

Androgenetic alopecia is in part caused by elevated levels of androgens [2] which is a form of testosterone. High levels of testosterone are seen in women with PCOS and so hair loss can be one symptom of this condition. Low thyroid levels can also cause thinning hair and can cause hair loss on the outer ⅓ of your eyebrows. 


Androgenetic alopecia may also be related to a specific gene variation – AR – that can lead to increased activity of androgen receptors in hair follicles. 


One hugely overlooked contributor to Alopecia Areata and Universalis is pathogens in the body particularly Candida overgrowth.  Candida can also cause vaginal yeast infections, athlete’s foot, eczema and psoriasis.  Parasites, another pathogen, can also cause some hair loss which is in part due to lack of nutrient absorption. 

Environmental Toxins

Having a high toxic load on your body can also cause hair loss. For instance heavy metal toxicity, such as mercury [4] from eating fish with high levels of mercury can cause hair loss. Mercury poisoning can also be from silver dental amalgams or from mercury vapor exposure in certain industries. 

Nutrient Deficiency

Nutrient deficiencies can also cause hair loss [3]. Women experiencing sudden weight loss due to restricted calories including low protein for instance can experience hair loss. B vitamin and Iron deficiency can also lead to hair thinning. If the body doesn’t get enough nutrients to perform optimally, it starts to pull back on non-essential activities such as hair growth in order to function properly. 

If you’re experiencing hair loss, it’s important to understand what type of hair loss it is and identify the most obvious causes. Be sure to go to your dermatologist if you’re uncertain about the type of hair loss you have. Once you determine this, you can start to heal the possible underlying root causes whether it be stress, toxins, pathogens, hormone imbalances or nutrient deficiencies.  

I work with hair loss clients to uncover underlying root causes of their hair loss through functional medicine testing. Based on test results I work with my clients to rebalance their body. If you’re interested in working with me, book your free chat with me today

This information is provided for educational purposes only and is not intended to diagnose, treat or cure any disease. Consult your doctor for diagnosis and before you begin any treatment protocols.

[1] https://medlineplus.gov/genetics/condition/androgenetic-alopecia/#frequency

[2] https://www.ncbi.nlm.nih.gov/books/NBK430924/

[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5315033/

[4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6219226/


Related Post