The parathyroid is another gland in the neck responsible for producing hormones. It controls the levels of calcium in the body and is also prone to disorders involving abnormal amounts of hormone production.

Hyperparathyroidism occurs when excess hormone is produced, leading to an overabundance of calcium in the blood. Symptoms include osteoporosis, lack of energy, abdominal pain, kidney stones, bone and joint pain, depression, loss of concentration, nausea and vomiting. Surgery is the most common treatment, which is successful in more than 90 percent of cases.

When the parathyroid glands produce too little hormone, the condition is known as hypoparathyroidism. Low calcium levels in the blood cause an increase in phosphorous and a tingling or burning sensation in the fingertips, toes and lips; muscle aches and cramps; fatigue; weakness; anxiety; headaches; muscle spasms in the hands, arms, throat and around the mouth; depression; mood swings and memory loss. Calcium supplements and Vitamin D are useful in treating this condition.