Haemochromatosis is a disease caused by excess iron in the body. Iron is needed in the diet to maintain good health, particularly for making red blood cells that carry oxygen around the body. These red blood cells contain large amounts of iron. Lack of iron can cause anaemia but excessive iron is toxic. The body has few ways of disposing of unwanted iron, so it builds up in tissues causing damage and disease.

More and more people are being diagnosed with hereditary haemochromatosis without showing any symptoms. Symptoms can be difficult to spot, as they are often mild initially, with many potential causes. Fatigue and lethargy are common, and joint pain or arthritis may occur. Sexual problems, particularly impotence in men or loss of menstruation in women, may be an important early sign.

As the iron overload increases, sufferers may experience the following diseases.
Liver disease
the liver is the main site of excessive iron build up. The disease causes scarring or liver fibrosis leading to cirrhosis. Symptoms include abdominal pain, jaundice, swelling of the ankles or abdomen and enlargement of the liver or spleen. In severe cases bleeding from the gut or coma can occur.

Heart disease
excess iron deposits may lead to one of two heart conditions. These are heart failure (indicated by tiredness, lack of energy, shortness of breath and ankle swelling) and abnormal heart rhythms. Patients may experience extra heart beats known as ectopics or disorders where the heart goes either too fast (tachycardia) or too slow (bradycardia).

Pancreatic disease
sugar diabetes (diabetes mellitus) may be an early sign of haemochromatosis and develops in up to half of all patients with advanced disease. Diabetes is due to excess iron in the pancreas gland damaging the insulin producing cells. This complication together with the dark skin pigmentation that can occur has led to haemochromatosis sometimes being called 'bronze diabetes'.

Other rare symptoms
endocrine gland problems particularly with pituitary, thyroid or sex hormones can occur, as can skin and neurological disease.

Haemochromatosis is more common in Caucasian or white populations, with about 1 in 300 to 1 in 400 affected. About half that number are affected in black populations.

Men are more likely to have hereditary haemochromatosis and suffer from it at an earlier age, as women regularly lose iron in menstruation or use stores in pregnancy.