How malnutrition causes hair loss and alopecia areata

Are you experiencing hair loss in patches, thinning or shedding? You're not alone! 


Hair loss is a common concern affecting millions worldwide, with various factors contributing to its onset. After living with hair loss for over 25 years, I know that it is hard to pinpoint the exact cause and take steps to regrow hair naturally and sustainably. 

Luckily, after much trial and error and then taking a functional medicine (root cause) approach to regain my health, I have enjoyed healthy hair growth for over nine years. 

One significant but often overlooked aspect of hair loss is malnutrition, particularly in cases of alopecia areata, an autoimmune condition characterised by patchy hair loss. 

In this article, I delve into the intricate relationship between malnutrition and hair loss, emphasising the role of specific nutrients and the impact of gut health on nutrient absorption.

Malnutrition and hair loss

As you may know, malnutrition occurs when the body lacks the essential nutrients necessary for optimal function. In the context of hair health, insufficient intake or absorption of vital nutrients can lead to various types of hair loss, including alopecia areata. While genetics and other factors play a role, addressing malnutrition is crucial in managing and preventing hair loss.

When I work with clients with alopecia areata, I find many of them have nutrient deficiencies which are essential for immune health and hair growth. Increasing their vitamin and mineral levels can make a big difference in how they feel and support them in regaining healthy hair growth. 

The Cell Health test (Metabolomix) offered at The Autoimmunity Nutritionist Clinic not only tests for these critical nutrients but also provides insight into the underlying cause of these deficiencies, such as digestive problems, candida overgrowth, toxicity, neuroinflammation, and blood sugar regulation issues. You can find out more about this testing package here

Five common nutrient deficiencies for hair loss

When it comes to malnutrition, I often find five nutrient deficiencies that come up repeatedly in hair loss cases. Below, I share the top five nutrient deficiencies I have recently seen in my clients with alopecia areata.  


Hair is primarily composed of a protein called keratin. Adequate protein intake is vital for hair growth and strength. Sources include lean meats, fish, eggs, dairy, legumes, and nuts. 

In particular, glycine, an amino acid abundant in collagen, is often highlighted as a deficiency in my client’s test results. Glycine plays a crucial role in hair growth due to its involvement in protein synthesis and collagen formation. 

Additionally, glycine aids in producing antioxidants that protect hair follicles from oxidative stress, a common contributor to hair damage and loss, which may be why immune tolerance is lost at the hair follicle in alopecia areata. 

Bone broth, gelatin, meat (especially pork and poultry), seafood, and dairy products are good sources of glycine. Opt for organic where you can, and if you are eating dairy, goats' and sheep's milk is less likely to trigger inflammation in those who are susceptible.


Iron deficiency is associated with telogen effluvium, which is hair loss characterised by excessive shedding but not autoimmune-related. 

Iron deficiency can cause anaemia, which can exacerbate alopecia areata by contributing to insufficient oxygen supply to hair follicles, hindering their growth and leading to increased hair loss.

Iron-rich foods such as red meat, poultry, fish, lentils, and leafy greens should be included in the diet.

However, certain microbes also like to feast on the iron in your body, so if you live with chronic infections, you are more likely to become deficient regardless of your dietary intake. 

Blastocystis, a microscopic parasite commonly found in the human gut, can lead to anaemia by causing inflammation and damage to the intestinal lining, impairing nutrient absorption, including iron. 

Additionally, Blastocystis infection may trigger gastrointestinal symptoms such as diarrhoea and malabsorption, further exacerbating the risk of anaemia due to reduced iron uptake from the diet.

Blastocystis is tested for in the stool test I offer in my clinic, which can be extremely helpful when I am working with clients who have alopecia areata and aneamia to understand the root cause of their symptoms. You can learn more about my gut health testing package here

Omega-3 fatty acids

Omega-3 fatty acids support immune tolerance at the hair follicle by reducing inflammation and regulating immune cell activity, helping to prevent autoimmune reactions that can lead to conditions like alopecia areata. 

Their anti-inflammatory properties contribute to a balanced immune response, protecting the hair follicles from attack and promoting healthy hair growth.

Oily fish like salmon, flaxseeds, chia seeds, and walnuts are excellent sources of omega-3 fatty acids.

Vitamins A and C

Both vitamins A and C play key roles in collagen production, which is essential for hair structure and growth. 

The active form of vitamin A, retinol, is crucial for healthy hair growth as it regulates gene expression and promotes cell differentiation in hair follicles; however, some individuals may have genetic variations or conditions that impair their ability to efficiently convert beta-carotene into retinol, reducing their access to this essential nutrient for hair health.

Foods rich in vitamin A include carrots, sweet potatoes, and spinach, while citrus fruits, strawberries, and bell peppers are excellent sources of vitamin C.

However, the active form of vitamin A retinol can be found in animal-derived foods such as liver, eggs, dairy products, and oily fish like salmon, providing a readily available source for supporting healthy hair growth. Cod liver oil is also a great source of this vitamin. 


Zinc plays a crucial role in alopecia areata by modulating immune responses, specifically by regulating T lymphocytes, which are involved in autoimmune reactions targeting hair follicles. 

Adequate zinc levels help maintain immune tolerance, reducing the risk of autoimmune attacks on hair follicles. 

Oysters, beef, lamb, pumpkin seeds, chickpeas, and lentils are good dietary sources of zinc, which can support immune function and potentially alleviate symptoms of alopecia areata.

But remember, even if you eat a lot of nutrient-dense foods and take copious amounts of supplements, you can still become deficient if you don't break them down and absorb them. Gut health plays a vital role in nutrient absorption. Even with a nutrient-rich diet, malabsorption due to gut issues can lead to deficiencies and subsequent hair loss. 

Conditions such as leaky gut syndrome, coeliac disease, and inflammatory bowel disease can impair nutrient absorption, exacerbating malnutrition-related hair loss, so if you are experiencing hair loss, it is always best to check your digestive health as well. 

Addressing malnutrition is essential for maintaining healthy hair, especially in cases of alopecia areata. By ensuring adequate intake of critical nutrients and supporting gut health, you can improve your chance of preventing and managing hair loss. 

And if you would like to learn more about the role of nutrition in healthy hair growth, then be sure to join Nutrition Essentials for Healthy Hair Growth on at 8pm on Wednesday 15 May 2024. You can learn more about this free event here.

And if you would like to learn how nutritional therapy and functional medicine could help with your hair loss and autoimmune symptoms, please book a free initial consultation with me.

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

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London W1G & Harrogate HG1
Written by V. J. Hamilton, Autoimmune Disease Expert | BSc (Immunology), DipION, mBANT
London W1G & Harrogate HG1

After 25 years of suffering from multiple autoimmune conditions including alopecia, psoriasis and CFS, VJ discovered she could uncover the root cause of her issues to transform her health & live without symptoms.

VJ now uses these same principles to help those with autoimmune diseases regain their strength & live a whole and symptom-free life.

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