Health and Disease

What Hair Can Say About Your Health

Conditions and medications affect our bodies as well as our hair. The way our hair feels, looks, and behaves reveals more about our health than initially meets the eye. Drastic changes in your hair could indicate nutritional and health issues.

Dry and Dull Hair

Dry and dull hair could indicate a lack of unsaturated fats in your diet. 

These are vital because they promote healthy skin and a healthy scalp, which revitalizes your strands. Contrary to popular belief, curlier and kinkier hair (types 3A-4C) are naturally more prone to being drier, as coils make it harder for hair’s natural oils to coat and moisturise each strand.

You can improve your hair by including avocado, olive oil, and salmon into your diet, as well as using argan, olive, or black castor oil on your hair.

Brittle Hair

Naturally curly hair tends to be more fragile than straight hair. Due to the uneven shape of the fibre, the hair shaft has spots where the internal structure becomes exposed, leaving the hair vulnerable to damage and dehydration. Although everyone’s locs need moisture, extremely brittle hair can actually be a sign of a zinc or an iron deficiency. Zinc and iron are important in the production of keratin, the main structural fibrous protein that hair is made up of, and having an insufficient amount can lead to changes in the structure of hair. To combat brittle hair, you could take zinc supplements, alone or with a mineral formula including iron, or you could eat foods that are high in zinc (e.g. beef, pumpkin seeds, and lentils). 

Having brittle hair could also be one of the many symptoms of Cushing’s syndrome, a rare condition caused by too much cortisol, the body’s primary stress hormone, alongside high blood pressure, fatigue, and back pain.

Thinning and Shedding Hair

Thinning hair could mean your diet lacks protein.

Hair is made of protein and needs adequate protein levels to be healthy. Made up of keratin, the aforementioned fibrous protein, hair can thin or deplete in overall health due to calorie cuts in your diet. It is not a perfect measure, but some experts estimate that we may shed up to 100 or more hairs a day. For adult males, balding is at a higher rate, but genes cause 90% of male hair loss

Sudden shocks and changes to your body’s system such as chemotherapy, giving birth, diets, severe stress, and thyroid problems can push hair into its resting, or telogen, state. Excessive shedding could indicate a more serious condition. Lack of iron (anemia), thyroid diseases, vitamin D deficiency, and low ferritin levels are a few things doctors may look into when severe hair loss is being reported out of ‘nowhere’.. A general rule of thumb is if you are experiencing hair loss and your ferritin is below 40 ng/mL, it’s a good idea to supplement. Too much or too little testosterone in women can also have negative effects for hair loss. In alopecia areata, your immune system mistakenly attacks hair follicles, causing hair to fall out. Most patients will have one or two bald patches, which can be treated easily with injections.

Premature Greying

Greying is part of the natural aging process, however, early and premature greying may not be. Genetics might play a part, but in some cases, the lack of pigment in hair at a young age can indicate a copper deficiency. We do not need too much copper in our diets however, it is suggested to add more mushrooms, sesame seeds, and seaweeds to combat the deficiency.

Stress is constantly labelled as the biggest killer, and a prevalent root of many health complications, including premature greying. Oxidative stress, in particular, may affect pigment-producing cells.

Hair For Drug Tests

Hair can be used in forensics to test for an extremely extensive range of substances: cannabis, cocaine, opiates, amphetamines, methamphetamines, benzodiazepines, methadone, mephedrone and ketamine. Drugs in the bloodstream can be recognised between 7 days and 6 months after their use. Test results also indicate the month someone ingested the substance and can be used to build an estimated timeline of substance use. In case the hair is unsuitable for testing, such as highly bleached or damaged, body hair or fingernails can also be used, as they are made of the same fibrous proteins.

Nara Ito, Youth Medical Journal 2021


  1. Nayak, B. S., Ann, C. Y., Azhar, A. B., Ling, E., Yen, W. H., & Aithal, P. A. (2017). A Study on Scalp Hair Health and Hair Care Practices among Malaysian Medical Students. International journal of trichology, 9(2), 58–62.
  2. St Pierre SA, Vercellotti GM, Donovan JC, Hordinsky MK. Iron defi ciency and diffuse nonscarring scalp alopecia in women: more pieces to the puzzle. J Am Acad Dermatol. 2010;63:1070–6.
  3. Trost LB, Bergfeld WF, Calogeras E. The diagnosis and treatment of iron defi ciency and its potential relationship to hair loss. J Am Acad Dermatol. 2006;54:824–44.
  4. Rushton DH, Dover R, Norris MJ, Gilkes JJH. Iron and hair loss in women; what is deficiency? This is the real question! J Am Acad Dermatol. 2007;56:518–9; author reply 519.
  6. Usman, M., Naseer, A., Baig, Y. et al. Forensic toxicological analysis of hair: a review. Egypt J Forensic Sci 9, 17 (2019).
  7. Marrinan, S., Roman‐Urrestarazu, A., Naughton, D., Levari, E., Collins, J., Chilcott, R., … & Corazza, O. (2017). Hair analysis for the detection of drug use—is there potential for evasion?. Human Psychopharmacology: Clinical and Experimental, 32(3), e2587.
  8. Hara, M., Kovacs, J., Whalen, E. et al. A stress response pathway regulates DNA damage through β2-adrenoreceptors and β-arrestin-1. Nature 477, 349–353 (2011).

By Nara Ito

Nara Ito is a student from London, England. She is interested in neurology, immunology, and genetics

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