There are four small parathyroid glands located behind or within the thyroid. They control the use of calcium and phosphorus (as phosphate) in the body’s metabolism. An imbalance of these vital elements can lead to tetany (muscular spasms), or at the other extreme, calcium may be transferred from the bones to the blood, creating a tendency to bone fractures and breaks.
The reflexes to these glands are found in the same location as those for the thyroid but it will probably be necessary to massage more strongly to achieve and effect. It is a good idea to work on these areas each time reflexology is undertaken as they are vital in maintaining the metabolic equilibrium of the body.
The thymus is located in the neck (over the breastbone) and is a vital contributor to the immune system. It is larger in children and is important in the development of the immune response. After puberty it shrinks although seems to become more active later in life. Bone marrow cells mature within the thymus and one group, T-lymphocytes, are dependent upon the presence of the thymus. These are important cells as they produce antibodies.
The commonest disorder associated with the thymus is myasthenia gravis, which lowers the level of acetylcholine (a neurotransmitter) resulting in a weakening of skeletal muscles and those used for breathing, swallowing, etc. The thymus reflexes are found on the soles of the feet and palms of the hand, next to the lung reflexes the thymus can also be stimulated by tapping with the finger over its position in the middle of the upper chest.