Nails Indicate Health Status

    Nails are often referred to as the ‘barometer of overall health’. Everything one sees on the outside of the body is a reflection of something going on inside. The significance of nails as indicators of health status has been recognised as early as the 5th century B.C. when Hippocrates first described clubbing (a deformity of the nails) as a symptom of disease.

    The colour, texture and shape of the nails reflect the general health of an individual, which may signify underlying systemic diseases. Trauma to the nails should always first be excluded, as well as a thorough physical examination to substantiate any health concerns. However, not every change in the colour or texture of the nails indicates a systemic disease. Old age causes nails to become drier, more brittle and less flexible, due to its loss of moisture and suppleness; damage to the nail changes the colour to purple/black; certain drugs and chemotherapy agents may also alter the colour of the nails, and heredity may also be a factor to consider.



    Keratin is a protein and is the key structural component of nails. Between the keratin layers are fat molecules and water, which give nails their pliability and shiny appearance. Food intolerances and nutritional deficiencies, such as a depletion of sulphur in the amino acids, interfere with the binding of keratin, which is responsible for the hard covering of the nail. Nails which are too soft are more easily damaged and stained and are at risk of peeling or becoming pitted. Frequent exposure to water exposes the nail to becoming infected. Nail plates that become too flexible will lose their strength, whereas nail plates which are too hard will lose their flexibility. The strength of the nails must be balanced with flexibility.


    The growth of the nails is also an indicator of health status, which is dependent on many factors, including illness, stress, age and biting or improper cutting. The average fingernail growth is 3 mm per month, or about 0.1 mm per day, which requires about six months for complete regrowth, thereby visually portraying the health of a person over this period of time. Toenails take about 12 to 18 months to regrow, which is two to three times as long as fingernails.


    Ridges on nails may be either vertical or horizontal and are considered to be quite common. Although ridges could occur as a result of heredity, trauma or ageing, they may also indicate systemic diseases, such as anaemia or kidney disease. With age, the natural oils of the skin decrease, causing dryness of the nails and cuticle, resulting in ridges.

    A deficiency of vitamins A, B, especially biotin, C, and minerals such as silica, phosphorus, sulphur, calcium and iron, can also result in ridges. Malnutrition, as well as malabsorption, from an inability of the body to absorb essential nutrients, minerals and vitamins, can also result in nail ridges. Longitudinal ridges may also be associated with deficiencies in the essential fatty acids, namely those of linoleic alpha-linoleic and arachidonic acids, formerly known as vitamin F. A central nail ridge may indicate a deficiency of iron, folic acid or protein. However, a central nail canal (Heller’s line) may be associated with repetitive trauma, severe malnutrition, or peripheral vascular disease.


    Nail colour should be a healthy pink, and any changes may reveal diseases, usage of certain drugs, nutritional deficiencies or a reaction of the body to cold or trauma. Green nails can be caused by allergies from cleaning agents, bacterial and fungal infections, as well as advanced emphysema, due to a severe lack of oxygen in the bloodstream. Blue nails may indicate a constriction of blood supply due to coldness, or from cardiac/pulmonary conditions, or iron deficiency. A yellow-red patch on the nail gives the appearance of an oil drop spot, as in psoriasis. Reddish-brown spots can indicate a deficiency of folic acid, protein or vitamin C.

    Yellow nails may result from nicotine stains, fungal infections, tetracycline drugs, rheumatoid arthritis, or hypoalbuminaemia (a deficit of the protein albumin in the blood). White nails may be indicative of anaemia, vascular conditions or oedema. Red nails may occur as a result of polycythemia, carbon monoxide poisoning, angioma, or malnutrition. Black/brown grey nails usually indicate trauma, but may indicate systemic diseases, such as anaemia, vitamin B12 deficiency, bacterial infection, chronic kidney disease, adrenal gland problems, liver disease, breast cancer or melanoma, or silver deposits from heavy metals.

    Vascular changes of the nails

    Terry’s nails are recognisable by the extension of the lanula (moon-shaped crescent) to 75% of the nail, leaving only a distal brown arc. It occurs in states of stress, such as advanced age, liver diseases, chronic renal failure, congestive heart failure, non-insulin dependent diabetes, hyperthyroidism and malnutrition.

    Lindsay’s nails are represented by the lanula which extends to roughly 50% of the nail, with the rest of the colour being a brown transverse band. This is associated with chronic renal disease, uraemia, and renal transplant patients on haemodialysis, as well as HIV.

    Mee’s lines are characterised usually by a single, transverse, narrow whitish line that runs the width of the nail plate, and may be seen on single or multiple nails. This may occur as a result of arsenic, carbon monoxide or thallium poisoning, or other heavy metals, or after an acute illness or chemotherapy. They are also found in Hodgkin’s disease, and congestive heart failure.

    Muehrcke lines are narrow double white transverse lines, which do not grow out, because the lesion is in the nail bed. This may be due to trauma, decreased protein synthesis or protein deficiency, kidney disease, liver disease, or chemotherapy. When albumin levels are normalised, the lines disappear.

    Beau's lines are deep horizontal (transverse) depressions in the nail plate that run parallel to the lanula, which can be single or multiple, and which do grow out. They usually occur after an acute severe illness and infections such as pneumonia, myocardial infarction, or even emotional stress, but can also be a sign of zinc deficiency. Other causes may include Raynaud’s disease, trauma, chemotherapy, or exposure to cold.

    One can determine when the illness occurred by looking at the location of the line. As nails take six months to grow out, if the line is half way up the nail, the illness would have occurred three months previously. The interruption of nail growth may also occur after shock, malnutrition and weight loss.

    Koilonychia, or spoon-shaped nails

    Spoon-shaped nails reveal either iron deficiency or too much iron. They are also associated with diabetes mellitus or protein deficiency, especially sulphur-containing amino acids, which occurs if the intestine is not absorbing the nutrients present in food properly. Pitting of the nails are tiny punctuated depressions on the surface of the nails, as in psoriasis, but may also be associated with reactive arthritis or alopecia areata (patches of hair loss). Clubbing of the fingernails is represented by a swollen nail base which loses its diamond-shaped appearance. There are numerous causes, amongst which are cardiac, pulmonary, intestinal and hepatic.


    Nails and hands should be kept clean, dry, and moisturised with vitamin E, almond, jojoba or olive oil. Oil slows down the passage of water through the nail plate and it does not evaporate as fast as water, which increases moisture content, thereby making nails more flexible and durable. Products which contain mineral oils are not readily absorbed into the skin and nails.

    Protect nails from trauma, which includes not picking or biting them, or using them as tools to pick up, poke or pry things, which causes abnormal nail growth or deformities. Protect hands from the cold, or when working with water, by wearing gloves.

    Do not push back cuticles or dig out ingrown nails, which damages the nails and increases the risk of infection.

    Nails should be cut in a square shape, by trimming them straight across the nail, so as to prevent damage as well as ingrown nails. An emery board will smooth off any rough edges, with a slight rounding off of the tip of the nail; nails should be filed in one direction. Shoes should not be worn too tight as this can cause ingrown nails.

    Nails Indicate Health Status


    Healthy eating patterns and lifestyle habits play an integral role in metabolic efficiency and overall health, and vitamin and mineral content must be absorbed and assimilated by the body. The diet should consist of fresh, minimally processed and refined foods. Vegetables and whole grains are particularly beneficial for strong and healthy nails.

    Essential fatty acid omegas-3 is found in fish oil, flaxseed oil, evening primrose oil and borage seed oil. This moisturise the nail bed, which increases nail flexibility, especially for thin and brittle nails.

    As nails are composed of keratin and protein, they require the tissue-building sources of protein. Foods which are high in protein include: turkey and chicken breast, tuna, salmon and halibut, cheese, pork, beef and veal, tofu, beans and mature soy beans, eggs and especially the white of eggs, yoghurt, milk and soymilk, and the seeds of pumpkin, watermelon, peanuts and almonds. Vegetarians can obtain good sources of protein through tofu, fish, beans and legumes.

    Adequate amount of water intake is essential for optimal functioning of the body, together with exercise, stress reduction, sleep, fresh air and elimination of waste products from the body and retention of valuable nutrients.


    Look after your health and you will see the result reflected in your perfect nails. Should any health nail abnormalities persist, visit a doctor or dermatologist as soon as possible.

    ‘Nails are like the mirror of the soul. Take care of the soul, and the nails will shine!’ ~Dr Linda Mayer

    Editor's note: If you enjoyed this article, then I am sure you will enjoy this one: Optimal Nutrition for Hair, Nails and Skin

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