What is the link between parasites, histamine and alopecia?

When you first notice a patch of hair loss — or when someone like your hairdresser points it out — the first question people often ask is whether you're stressed. It’s a natural reaction, as stress is a well-known factor in hair loss.

I remember when I first visited a dermatologist at the age of seven, the first thing they asked was if I was stressed about anything. The truth is, I was. My life was full of changes, and I placed a lot of undue pressure on myself at school. But while stress can certainly contribute to hair loss, it’s often just one piece of the puzzle. Something more complex and potentially more sinister could be beneath the surface and be at the root of the issue. 

Alopecia aeata is an autoimmune condition characterised by unpredictable hair loss, often appearing as small, round bald patches on the scalp. The exact cause of this condition remains elusive, but emerging research points to a surprising connection between gut health and hair loss. 

As an autoimmune expert and nutritionist, I’ve observed through my clinical practice and seeing 100s of clients with alopecia areata, a growing link between gut parasites —specifically blastocystis and dientamoeba — and the development of alopecia areata. These parasites may contribute to histamine intolerance, elevated eosinophils in stool tests, inflammation, nutrient deficiencies, and ultimately, hair loss.

The role of gut parasites in alopecia areata

Gut parasites like blastocystis hominis and dientamoeba fragilis are common parasites often overlooked as potential contributors to autoimmune conditions, including alopecia areata. These parasites can disrupt the gut’s delicate balance, leading to a cascade of immune responses that manifest in various ways, including hair loss.

Histamine intolerance and hair loss

One key way that gut parasites can contribute to alopecia areata is through histamine intolerance. Histamine is a naturally occurring compound in the body that plays a role in immune responses, digestion, and the central nervous system. However, when the body is unable to break down histamine effectively due to factors like parasite infections, histamine levels can become elevated, leading to a range of symptoms, including inflammation.

These parasites can disrupt the gut barrier, causing intestinal permeability or leaky gut, which allows undigested food particles and toxins to enter the bloodstream. This activates immune cells, such as mast cells, which release histamine. Elevated histamine levels can exacerbate inflammation and contribute to symptoms of histamine intolerance. A study found that Blastocystis infection is associated with increased mast cell activation and histamine release, linking parasitic infection to heightened histamine responses.

Histamine intolerance can trigger an overactive immune response, which is particularly problematic for individuals with autoimmune conditions. In the case of alopecia areata, elevated histamine levels may exacerbate the immune system’s attack on hair follicles, leading to increased hair loss.

I commonly work with clients, both adults and children, with alopecia who are not only experiencing patchy hair loss but also have blocked sinuses, watery eyes and itchy skin. 

Eosinophils and Inflammation 

Eosinophils are a type of white blood cell involved in the body’s response to allergens and parasites. Elevated eosinophil levels, which you can identify in a stool test, indicate an immune response to gut parasites. This is significant because high eosinophil counts are associated with inflammation, a known trigger for autoimmune conditions like alopecia areata.

The marker associated with elevated eosinophils in a stool sample is eosinophil protein X (EPX). When parasites are present, eosinophils release EPX to combat the infection, but this also contributes to inflammation in the gut. When a parasite is identified in one of my clients’ stool test results I always check their EPX levels to understand how much their immune system is reacting to these parasites in this way.

Nutrient deficiencies and low ferritin

Gut parasites can also interfere with the absorption of essential nutrients, leading to deficiencies that may contribute to hair loss. For instance, low ferritin levels (a marker of iron stores in the body) are commonly linked to hair thinning and loss. Parasites can cause malabsorption of iron, leading to low ferritin and subsequent hair loss.

Iron is crucial for hair growth because it supports the production of haemoglobin, which carries oxygen to hair follicles. Without adequate iron, hair follicles become deprived of the oxygen they need to function correctly, resulting in hair loss.

Key signs of low iron, or iron deficiency, include fatigue, weakness, pale skin, shortness of breath, and dizziness. You might also experience cold hands and feet, brittle nails, and unusual cravings for non-nutritive substances like ice or dirt (a condition known as pica). 

Moreover, parasites can contribute to deficiencies in other vital nutrients, such as B vitamins, zinc, and magnesium, all are vital for maintaining healthy hair. The combination of nutrient malabsorption, chronic inflammation, and an overactive immune response creates a perfect storm for developing alopecia areata.

Natural therapies for hair loss associated with gut parasites

Addressing the root cause of hair loss in those with alopecia areata involves a multifaceted approach, including natural therapies aimed at restoring gut health and supporting hair regrowth.

When I work with clients I aim to take a personalised approach, however, there are steps that most people will need to take when addressing parasites in their gut. 

Step 1: Gut protocol 

The first step in addressing gut parasites is implementing a comprehensive gut healing protocol. This typically involves using antiparasitic herbs such as oregano, berberine, and wormwood, effectively eliminating parasites from the gut. Additionally, incorporating probiotics and prebiotics can help restore healthy gut flora, reduce inflammation, and improve nutrient absorption.

Step 2: Nutrient replenishment

To combat nutrient deficiencies, it’s essential to replenish depleted stores of iron, B vitamins, zinc, and magnesium. This can be achieved through a combination of dietary changes and targeted supplementation. Consuming iron-rich foods such as grass-fed red meat, leafy greens, and lentils, along with a high-quality iron supplement, can help raise ferritin levels and support hair regrowth.

Step 3: Anti-inflammatory diet:

An anti-inflammatory diet is crucial for reducing the overall burden of inflammation in the body. Focus on whole, unprocessed foods rich in antioxidants, such as berries, leafy greens, and oil fish. Avoiding common inflammatory foods, such as refined sugars, processed grains, and dairy, can also help alleviate symptoms of histamine intolerance and reduce hair loss.

Step 4: Histamine-lowering strategies:

Managing histamine intolerance involves both dietary changes and lifestyle modifications. A low-histamine diet, which eliminates or reduces foods high in histamine (such as aged cheeses, fermented foods, and alcohol), can be beneficial. Additionally, supporting the body’s natural histamine breakdown with supplements like vitamin C, quercetin, and DAO (diamine oxidase) enzymes can help manage histamine levels and reduce hair loss.

Step 5: Stress management and lifestyle:

Chronic stress can exacerbate gut issues and autoimmune conditions. Stress management techniques such as mindfulness, meditation, and regular physical activity can help modulate the immune system and support overall health, including hair health.

The role of stool testing in identifying root causes

Stool testing is a valuable tool for identifying the presence of gut parasites, histamine intolerance, and elevated eosinophils, all of which may contribute to alopecia areata. By analysing stool samples, we can gain insight into the health of the gut microbiome, detect parasitic infections, and assess levels of inflammation markers.

Armed with this information, we can develop a targeted treatment plan to address the underlying causes of hair loss rather than simply treating the symptoms. Stool testing can also monitor progress, ensuring that interventions are effective in restoring gut health and supporting hair regrowth.

The connection between gut health and hair loss is a critical yet often overlooked aspect of managing alopecia areata. Addressing gut parasites, managing histamine intolerance, and replenishing essential nutrients can mitigate hair loss and promote regrowth. 

As an autoimmune expert and nutritionist, my goal is to empower those with alopecia areata to take control of their health by exploring the root causes of their condition and implementing natural, effective therapies for lasting results.