Reference

Deficiencies

What happens when a nutrient runs short — and where it shows.

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Calcium deficiency

Chronic low calcium weakens bones and can disturb muscle and nerve function.

Folate (B9) deficiency

Low folate impairs cell production, causing anaemia and — in pregnancy — birth defects.

Iodine deficiency

Without enough iodine the thyroid cannot make hormones, slowing metabolism.

Iron-deficiency anaemia

Too little iron means the blood cannot carry enough oxygen, causing tiredness and pallor.

Magnesium deficiency

Low magnesium can trigger cramps, fatigue and heart-rhythm problems.

Potassium deficiency (Hypokalaemia)

Low potassium disturbs muscle and heart function.

Selenium deficiency

Low selenium can affect the heart, thyroid and immune function.

Vitamin A deficiency

Low vitamin A impairs vision and immunity and dries the skin and eyes.

Vitamin B1 deficiency (Beriberi)

Thiamin deficiency affects the nerves and heart and, with alcohol, the brain.

Vitamin B12 deficiency

A shortage of B12 harms red blood cells and nerves, causing anaemia and neurological signs.

Vitamin B2 deficiency (Ariboflavinosis)

Low riboflavin shows up around the mouth, tongue, eyes and skin.

Vitamin B3 deficiency (Pellagra)

Niacin deficiency causes the classic "three Ds": dermatitis, diarrhoea and dementia.

Vitamin B6 deficiency

Low B6 can cause anaemia, skin changes and nerve or mood symptoms.

Vitamin C deficiency (Scurvy)

Severe vitamin C shortage breaks down collagen, causing bleeding gums and poor healing.

Vitamin D deficiency

Low vitamin D weakens bones and muscles and can affect immunity.

Vitamin E deficiency

Rare, but low vitamin E can damage nerves and muscles over time.

Vitamin K deficiency

Low vitamin K impairs blood clotting, causing easy bleeding and bruising.

Zinc deficiency

Too little zinc weakens immunity, slows healing and can affect taste and skin.
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