Hypocalcaemia

What is hypocalcaemia ? (too little calcium)

Calcium is a mineral that's vital for the development of healthy bones and teeth - 99 per cent of the calcium in our bodies is found here. It's also needed for muscle contraction, regulation of the heartbeat and formation of blood clots. A long-term shortage of calcium can lead to osteoporosis (brittle-bone disease).

The four pea-sized parathyroid glands (found at the front of the neck) are responsible for regulating the body's calcium levels. These small glands, which are embedded in the tissue of the thyroid gland in the neck, detect fluctuations in the level of calcium in the blood.

There are times when this delicate balance is upset and levels of calcium fall too low. When the levels drop, the glands secrete parathyroid hormone (PTH). This causes calcium to be released from the bones, more to be reabsorbed through the kidneys and more to be absorbed from food in the intestines.

Symptoms

A shortage of calcium in the blood may cause:

• Tetany (muscular spasm) in the hands, feet or sometimes even the throat throat causing problems swallowing and voice changes
• Depression
• Numbness and tingling in the hands, feet or around the mouth
• Seizures

Causes and risk factors

Hypocalcaemia may be caused by chronic kidney failure, pancreatitis or problems with the parathyroid glands, which mean they don't produce enough PTH.

This last condition, hypoparathyroidism, often occurs after damage to the parathyroid glands during surgery on the thyroid gland. Sometimes, however, it develops because of an autoimmune reaction when the body attacks itself.

The excessive breathing or hyperventilation that can occur during extreme anxiety can also disturb calcium levels. Hyperventilation makes the blood a little more alkali which changes disrupts the balance of calcium and cause the symptoms of hypocalcaemia (such as tetany) with no fall in total blood calcium levels.

Treatment and recovery

In the case of hypocalcaemia, when calcium levels are too low, calcium and vitamin D supplements are often required.

Vitamin D is needed to help the body absorb calcium. This is made under the skin in response to sunlight and can also be found in foods such as cod liver oil, mackerel, canned salmon, eggs and milk.

Good sources of calcium include:

• Dairy products
• Cheese
• Yoghurt
• Milk
• Canned fish
• Leafy green vegetables
• Fortified bread and cereals

If the symptoms are caused by hyperventilation, then treatment for underlying problems such as anxiety may resolve the symptom.