The thyroid, the small gland situated in the neck region, has four major hormones. They are stored in the thyroid and released as needed.

T4, or thyroxine is produced only in the thyroid itself, and is about 93% of all the thyroid hormone used in the body. Its main function is energy conversion, or as some would say, to speed up the metabolism.

The thyroid together with the pituitary and hypothalamus glands in the brain, form the HPA axis, a glandular highway.

When the thyroid functions properly, the body's temperature is normal and the metabolic functions are maintained. Stress, illness, fasting or elevated cortisol levels can cause dysfunction.

A malfunctioning thyroid (over or underactive) can lead to fatigue, muscle pain, weight problems and depression - check yours annually!

Ask your doctor for a thyroid check if he/she does not suggest it.