The gut-hair link: Are gut imbalances the root of alopecia?

For a quarter of a century, I lived with alopecia. Sometimes I would get spontaneous regrowth, but often when times were more challenging, it would shed again. But everything shifted when I began exploring my gut health.


At the time, I didn’t think I had an issue with my gut and that the constant pain and rumblings in my stomach were normal. However, I have enjoyed over eight years of consistent hair growth after focusing on healing my gut. 

It is incredible to see how deeply your gut health can influence other parts of your body, including your hair, which is why when I work with clients with alopecia, we often address their gut health first. 

As you may know, when it comes to hair loss, many factors are typically focused on as the cause: genetics, hormones, stress, and poor hair care routines. However, a growing body of research reveals a less obvious suspect: gut health. The health of your gut can influence the health of your hair. Let's delve deeper into this connection.

The gut-hair connection

Microbiome and nutrient absorption 

The gut microbiome is at the core of our digestive system, a diverse community of bacteria and microorganisms that help digest food and synthesise vital nutrients. A balanced gut microbiome ensures optimal nutrient absorption. Since healthy hair requires nutrients like vitamins E, A, and D, biotin, and minerals like iron and zinc, any imbalance in the gut can compromise hair health.

I often see clients with hair loss, who are already eating a fairly healthy diet, but they still have nutrient deficiencies. This rings alarm bells to me straight away, as I was in a similar position, and that’s when it is likely that digestive issues are at the heart of their nutrient deficiencies. 


An unhealthy gut can lead to systemic inflammation. Did you know that over 70% of the immune system is in the gut? Chronic inflammation has been linked to conditions such as telogen effluvium, a form of temporary hair loss. And as alopecia areata is an autoimmune disease, inflammation adds fuel to the fire and may exacerbate hair loss. By promoting inflammation, an imbalanced gut can indirectly impact hair health.

Gut permeability 

I am sure by now you have heard of leaky gut syndrome, which is a condition where the gut lining becomes permeable, allowing undigested food particles, bacteria, and toxins to enter the bloodstream. This can trigger autoimmune reactions through a concept known as molecular mimicry. Sometimes, the body may mistakenly target hair follicles, leading to conditions like alopecia areata.

Probiotics, prebiotics, and hair health

A diet rich in probiotics and prebiotics can help maintain a healthy gut microbiome balance. Probiotics are beneficial bacteria, and prebiotics are the fibres that feed them.


Found in fermented foods like yoghurt, kefir, sauerkraut, and kimchi, probiotics can help repopulate the gut with beneficial bacteria, potentially promoting better nutrient absorption and reducing inflammation.


Foods like garlic, onions, and bananas are excellent sources. They help feed the good bacteria, ensuring a balanced gut ecosystem.

Specific gut bacteria linked to alopecia

Did you know that the bacteria which are living in your gut, can be linked to hair loss?

Recent studies have increasingly emphasised the potential connection between gut bacteria imbalances and alopecia, particularly alopecia areata, an autoimmune condition that causes hair to fall out in small patches.

1. Lactobacillus and bifidobacterium

These are among the most studied probiotic bacteria and have shown promise in promoting hair health. They are known to reduce systemic inflammation, which can indirectly benefit those suffering from hair loss. A study published in the Journal of Applied Microbiology in 2019 demonstrated that oral administration of Lactobacillus and Bifidobacterium strains improved hair growth and density in mice.

2. Escherichia coli (E. coli)

Certain strains of E. coli are harmful and can cause digestive problems. Research has shown that individuals with alopecia areata had higher amounts of E. coli in their gut than those without the condition. This suggests a possible negative relationship between E. coli overgrowth and hair health.

3. Fusobacteria

Another bacteria found in higher amounts in individuals with alopecia areata is fusobacteria. While the specific role of this bacteria in hair loss isn't entirely clear, its abundance in those with alopecia suggests a potential link.

4. Decreased bacteroides

On the flip side, individuals with alopecia areata have been found to have reduced levels of bacteroides bacteria. These bacteria play a significant role in maintaining gut health and reducing inflammation, suggesting their decreased presence might harm hair health.

I offer my clients the GI Effects stool test, as part of the three-month Health Transformation Package. This test reveals the different levels of bacteria in the gut, as well as whether there is any malabsorption or inflammation present in the gut, that might be contributing to symptoms. Visit my profile if you would like to know more about the gut health functional testing package and how I work. Or you can book a free initial consultation with me.

The 3 Ps: Probiotics, prebiotics, and polyphenols

A diet rich in probiotics, prebiotics and polyphenols can help maintain a healthy gut microbiome balance. Probiotics are beneficial bacteria, prebiotics are the fibres that feed them, and polyphenols inhibit the growth of harmful bacteria and keep the immune system in check. 

Probiotics are found in fermented foods like yoghurt, kefir, sauerkraut, and kimchi, probiotics can help repopulate the gut with beneficial bacteria, potentially promoting better nutrient absorption and reducing inflammation.  A word of caution, not everyone’s gut is ready for fermented foods, so if you have a reaction after eating these foods, then it may be a sign of imbalances which need to be addressed before eating these foods. 

Prebiotics are foods like garlic, onions, and bananas are excellent sources. They help feed the good bacteria, ensuring a balanced gut ecosystem. It is best to eat a variety of these foods daily. 

Polyphenols, naturally occurring compounds found in plant foods like fruits, vegetables, and teas, play a crucial role in promoting a healthy gut. They foster the growth of beneficial bacteria, inhibit harmful ones, and support the immune system by modulating the gut bacteria composition. Polyphenol-rich foods include berries, apples, cherries, spinach, walnuts, cloves and green tea. 

Tips for a gut-friendly diet

1. Diverse diet

A varied diet rich in different foods provides a broad spectrum of nutrients and promotes a diverse gut microbiome.

2. Limit ultra-processed foods

Ultra-processed foods can disrupt the gut balance. Instead, focus on whole, natural foods.

3. Stay hydrated

Water is crucial for digestion and nutrient absorption.

While hair loss can be influenced by numerous factors, gut health shouldn't be overlooked. By nurturing the gut and maintaining a balanced microbiome, your body is in the best position to promote healthy hair growth. And by addressing the root cause of your hair loss, you are far more likely to have sustained hair growth for the long term.

In the Hair Growth Reviver digital programme, you will learn more ways to restore your gut function for better hair growth. If you are keen to do the programme with me, I am running it again live from the 9th of October and I would love to see you there! When I run the live programme not only do you get access to all the programme content, including a hair growth health plan and 8 modules, but you also get live weekly coaching calls. You can learn more by visiting my profile.

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

Share this article with a friend
London W1G & Harrogate HG1
Written by V. J. Hamilton, Autoimmune Disease Expert | BSc (Immunology), DipION, mBANT
London W1G & Harrogate HG1

VJ Hamilton is a qualified Nutritional Therapist and member of BANT, focusing on autoimmunity including inflammatory skin disorders, fatigue & neurological issues as well as gut health. VJ has a BSc in Biochemistry and Immunology which she uses in her practice, using only evidence-based nutritional therapies to support chronic conditions.

Show comments

Find a nutritionist dealing with Gut health

All nutrition professionals are verified

All nutrition professionals are verified