The parathyroid glands are small endocrine glands situated just below the thyroid glands in the neck. They are usually four in number, two behind each thyroid gland. They are very small, pea-sized and weigh about 50 mg. The glands function to maintain the calcium and phosphorus levels in our bodies.
Until the 20th century, scientists failed to recognise a gland separate from the thyroid glands, because of the small size of the parathyroid glands. Now, the two glands can be differentiated easily as the thyroid glands have a follicular structure, and the cells of a parathyroid gland are densely packed.
Functions of the Parathyroid Gland
The parathyroid gland releases a parathyroid hormone (PTH). Also known as the parathormone or parathyrine, it is a small peptide that maintains the homeostasis of calcium and phosphate and also aids in bone physiology. Let us see how this hormone functions.
- Calcium: The parathyroid hormone functions to release calcium from the bones by stimulating the osteoblasts. It facilitates gastrointestinal calcium absorption by activating Vitamin D. It also promotes calcium reabsorption in the kidneys. Normal calcium levels in the body support strong nervous and muscular systems.
- Phosphorus: It inhibits the absorption of phosphorus in the kidneys, however, the hormone increases the absorption of phosphorus in the gastrointestinal tract by activating Vitamin D.
- Activation of Vitamin D: The PTH also helps in the activation of Vitamin D by upregulating the enzyme 1-α-hydroxylase.
Disorders of the Parathyroid Gland
- Hyperparathyroidism: This condition is developed when an individual produces too much of the PTH hormone. Overproduction of the hormone releases large amounts of calcium, which causes hypercalcemia. The symptoms include extreme thirst, more urine production, abdominal pain and mood changes.
- Hypoparathyroidism: Low levels of PTH hormone causes hypoparathyroidism and hypocalcemia. The symptoms include tingling sensations, muscle cramps and spasms.
Undetected high levels of calcium lead to bone thinning or osteoporosis and can also cause stones in the kidneys.
Frequently Asked Questions
What happens if the parathyroid hormone is high?
What happens if the parathyroid hormone is low?
Low levels of parathyroid hormone lead to low levels of calcium that causes cramps and spasms in the body.
Can parathyroid affect your eyes?
The long term complication of hyperparathyroidism includes conjunctival calcification, conjunctivitis and corneal diseases.
What foods to avoid if you have parathyroid?
Refined foods and junk foods such as white bread, pizza, pasta and sugary items should be avoided if you have high levels of parathyroid hormone.
Should you take vitamin D if you have hyperparathyroidism?
Supplements should only be taken under the advice of medical experts.