The deficiency causes changes in the blood and the central nervous system.

However, it's not at all clear that deficiencies of these nutrients actually caused the asthma.

It is thought that this deficiency may cause or worsen depression in some people.

Deficiencies in vitamin C and calcium can cause dental problems.

A deficiency in any of these nutrients lead to our bodies not working at full capacity - and can even cause illness.

Check the vitamin/mineral list (page 9), as a deficiency in one of these can cause sleep problems.

Needs are distinguished from wants because a deficiency would cause a clear negative outcome, such as dysfunction or death.

In less developed countries severe deficiencies cause blindness in 250,000 children each year.

In addition, muscles require calcium to work efficiently so a deficiency can cause problems with hard working horses as well.

It is imperative to keep total potassium adequate because a deficiency causes the heart to lose force.