Reading the Signs!


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We all rely on the body to tell us when something is wrong. But are you making the most of the simple nutrition clues that the body gives you? Esther Mills looks at how your skin, hair and nails can help you to help yourself.

The skin is the body’s largest organ - about two square metres of it. Strictly speaking the hair and nails, which extend from the skin, are treated as part of the skin itself. However, whilst the skin is living, the visible part of the hair and nails, are not.
Although the skin, hair and nails all have specific functions, for nutritionists they provide vital clues about a person’s state of health. For instance, whether they have low or raised levels of vitamins, minerals and other essential nutrients, or whether they are run down, feverish, or stressed out. We have all heard about white marks on the fingernails being a sign of zinc deficiency, yet there are many other nutrients that affect the condition of the skin and its ‘extensions’.

How nutrition can affect skin, hair and nails.

So fundamental is the role of nutrition in optimal skin, hair and nail health, that these areas are the first to indicate nutrient inadequacies. This was known right from the early days of deficiency research, where low levels of vitamin C were seen to cause bleeding under the skin, and a deficiency of vitamin B3, to result in hyperkeratosis (hard, scaly skin). As time went by and interest in nutrition grew, practitioners began to recognise the value of spotting nutritional pointers by simply examining the external signs.

It is true that these symptoms are only observations of what ‘might’ nutritionally be the problem, but they act as time-tested clues of where a person’s nutritional status may be imbalanced.

These can then be confirmed with other means of diagnosis, such as a case history and tests, to come to a more definite conclusion.



The following A-Z guide gives useful information about how various nutrients affect the condition of the skin, hair and nails and how underlying health conditions may be discovered.

Ascorbic Acid (Vitamin C)
As already mentioned, a deficiency of vitamin C can cause skin soreness, easy bruising, poor wound healing and bleeding gums.
Good food sources: Berries, citrus fruit and green vegetables.

Beta carotene has an effect on the skin when levels reach about four times the normal amount. This gives a yellow/orange colouration to the skin, which is not harmful and is fully reversible when intakes are reduced.
Good food sources: Apricots, dark leafy greens. dulse, carrots, peaches, pumpkin, red peppers and sweet potatoes.

Cholecalciferol (vitamin D)
Vitamin D is well known as a skin nutrient, as this is exactly where it is synthesised from dehydrocholesterol into cholecalciferol, or ‘active’ vitamin D. In the winter, reduced amounts may contribute to thin, brittle nails. Vitamin D is sometimes used in the treatment of psoriasis.
Good food sources: Although vitamin D can be synthesised by the body, food sources include eggs, oily saltwater fish and dandelion greens.

Blood usually contains about l00pg of copper per l00mI. This mineral is vital for the formation of collagen and dastin within the tissue. Therefore a deficiency affects the overall suppleness of the skin.
Good food sources: Green leafy vegetables, avocado, broccoli, beans, lentils, nuts and raisins.

Cyanocobalamine (vitamin 812)
Some of the signs of a lack of vitamin BI 2 include poor hair condition, dermatitis and pale skin. A deficiency may result from malabsorption or possibly those following a vegan diet. Good food sources: Fish, sea vegetables and fermented Soya bean products.

Essential Fatty’ Acids
Lack of essential fatty acids can cause hair loss and thy, scaling skin as the skin layer becomes less fluid’ (flexible). Moisture is also lost, resulting in obvious signs of dryness. Nails can become thy as well, and may have ridges. Sometimes, a thick, keratinous layer develops on the skin, giving rise to eczema or prognosis. Good food sources: Dark leafy greens, seeds, nuts, wholegrains, soya beans, oily fish and cold-pressed vegetable oils.

Chronic iron deficiency causes spoon-shaped nails called koilonychia. This disturbs normal nail growth. Some practitioners have found that iron deficiency affects the hair. This is not proven with large clinical trials, but conditions which hinder iron metabolism have been shown to result in hair loss.
Good food sources: Green leafy vegetables, whole grains, dulse, almonds, raisins, dates and sesame seeds.

Manganese deficiency is rare, but can transpire in those on very restricted diets. Deficiency symptoms include dermatitis and poor hair and nail growth.
Good food sources: Avocado, nuts, seeds, seaweed and whole grains.

Niacin (vitamin B3)
Niacin (the collective name for nicotinic acid and its chemical derivatives) is important for healthy skin, hair and nails. Although deficiencies are said to be rare in the Western world, low intakes can occur in those on restricted, plant-based diets. This can cause sore, thy, cracked skin and may lead to skin eruptions. People with severe Chron’s disease may be prone to niacin deficiency, as their uptake of tryptophan (from which niacin can be made in the body) is impaired.
Good food sources: Broccoli, carrots, dandelion greens, dates, eggs, fish, potatoes, tomatoes and wholewheat.

Retinol (Vitamin A)
Retinol is important for the health of all skin surfaces. Its effect is described as ‘anti keratinizing’ - helping to keep the skin soft. When vitamin A is deficient, mucous-secreting cells are replaced by keratinocytes, cells which cause hardening and greatly increase the risk of infection. Normal lubrication is reduced, resulting in irritation. Vitamin A deficiency is characterised by plugged follicles, known as phrynoderma.
Good food sources: Although animal produce is the main source, vitamin A can be produced in the body from beta-carotene.

Research in China has shown that deficiencies of this nutrient, especially in children, can cause whitening of the nails.
Good food sources: Brazil nuts, sesame seeds, broccoli, onions, seafood and whole grains.

Vitamin B2, B and Biotin.
Deficiency symptoms for these B vitamins are very similar, causing dermatitis-like characteristics, and skin lesions. A deficiency can result from antibiotic use. A shortage of biotin can cause premature greying of the hair, as can Para-aminobenzoic acid (PABA), another B vitamin.
Good food sources: Fish, eggs, legumes, soya beans, whole grains, sunflower seeds and walnuts.

Zinc deficiency may lead to hair loss and thickening of the skin. There is a genetic condition linked to zinc shortage called parakeratoic disease, which results in red, scaling and obvious plaques on the skin surface. Another congenital disease that results in low levels of zinc is called acrodemiatitis enteropathica. Manifestations include fragile dry hair, alopecia and dermatitis. Reduced levels of zinc can also show up as eczema-type symptoms, stretch marks and white marks on the nails.
Good food sources: Fish, eggs, legumes, pumpkin seeds, sunflower seeds and whole grains.



An excess of this poisonous element can cause rain-drop’ pigmentations on the skin, hair loss and hardened skin on the palms of the hands and soles of the feet.
Sources: Contaminated drinking water, seafood, table salt, pesticides, tobacco smoke and smog.

Environmental pollution may give rise to high readings of lead in the body. Mild toxicity has been linked to blue gums. Chronic inhalation can lead to skin blistering.
Sources: Car exhaust fumes, water from lead pipes, paint and tobacco.

Too much cadmium in the body may show up as hair loss and scaly skin.
Sources: Seafood, cigarette smoke, paint, car exhaust fumes and industrial fumes.

Mercury toxicity may be hard to discover. Key signs, along with environmental questionnaires which look at mercury exposure, include very pink cheeks (hence it’s name ‘Pink disease’) hair loss, dermatitis and excessive salivation.
Sources: The prime source of mercury exposure is from amalgam fillings.


Use this chart as a quick reference guide to what your body might be telling you.

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Deficient nutrient

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Dry Skin

Yellow/orange colouration

Hardening of the skin

Spiral and unerupted hairs

Genitalia dermatitis

Burning skin (on feet)

Scaly skin

Excessive secretion (seborrhoea)

Cracked skin on the lips (Cheilosis)


Pale, sticky (pallor) skin

Scar tissue

Stretch marks
Vitamin C, vitamin K

essential Fatty acids, vitamin E

Excess beta-carotene

Vitamin A

Vitamin C

Vitamin B2,


Pantothenic acid

Vitamin B6

Vitamin B6

Vitamin B2

Vitamin B complex, essential fatty acids

Folic acid, vitamin Bi 2

Vitamin E

Vitamin E,


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Thin, brittle nails

Hard, thick nails

Split nails

Poor growth

Transparent nails

White spots and flecks

Deep ridges

Indents in the naiIs

White Nails

Vitamin D, essential fats, minerals

Excess of protein or fat

Sulphur-containing amino acids, vitamin A or EFAs



Zinc, vitamin B6

Zinc, iron B-complex or EFAs

Zinc, iron or calcium


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Very Dry hair


Dull or oily hair

General poor hair condition

Fragile, sparse hair

Very light hair

Hair loss

Premature greying
Copper, essential fatty acids

Vitamin A

Vitamin B2

Vitamin Bi 2, biotin


Iron or copper

Essential fatty acids, B complex, zinc, iron

Biotin, vitamin Bi 2, PABA

Did you know?
Toenail clippings can reveal more about you than you think! Researchers focusing on average intakes of selenium in the diet have used toenail clippings from thousands of subjects world-wide!

Baich, James and Phyllis.Prescription for Nutritional Healing, Avery 1997.
Mervyn, Dr Leonard.Signs and Symptoms of Vitamin Deficiency, Amber Publishing, first edition, 1995.
I.S Garrow, W.P.Tjames, Human Nutrition and Dietetics. Churchill Livzngstone, 9th Edition, 1993.
Holford, Patrick. The Whole Health Guide To Elemental Health, Thorsons 1983.



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