Obesity is a medical condition, sometimes considered a disease, in which abnormal or excess body fat has accumulated to such an extent that it may have a negative effect on health. People are classified as obese when their body mass index (BMI)—a measurement obtained by dividing a persons weight by the square of the persons height (despite known allometric inaccuracies)—is over 30 kg/m2; the range 25–30 kg/m2 is defined as overweight. Some East Asian countries use lower values to calculate obesity.Obesity is a major cause of disability and is correlated with various diseases and conditions, particularly cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. High BMI is a marker of risk for, but not a direct cause of, diseases caused by diet and physical activity. A reciprocal link has been found between obesity and depression, with obesity increasing the risk of clinical depression, and also depression leading to a higher chance of developing obesity.Obesity has individual, socioeconomic, and environmental causes. Some of the known causes are diet, physical activity, automation, urbanization, genetic susceptibility, medications, mental disorders, economic policies, endocrine disorders, and exposure to endocrine-disrupting chemicals. Epidemiologic studies of overweight and obesity in children and adults covering 195 countries have shown that the prevalence of obesity has steadily increased in most countries, doubling in 73 countries between the years 1980 and 2015. As of 2015, the United States and China had the largest numbers of obese adults, and China and India had the largest numbers of obese children.
Hyperparathyroidism is an increase in parathyroid hormone (PTH) levels in the blood. This occurs from a disorder either within the parathyroid glands (primary hyperparathyroidism) or as response to external stimuli (secondary hyperparathyroidism). Symptoms of hyperparathyroidism are caused by inappropriately normal or elevated blood calcium leaving the bones and flowing into the blood stream in response to increased production of parathyroid hormone. In healthy people, when blood calcium levels are high, parathyroid hormone levels should be low. With long-standing hyperparathyroidism, the most common symptom is kidney stones. Other symptoms may include bone pain, weakness, depression, confusion, and increased urination. Both primary and secondary may result in osteoporosis (weakening of the bones).In 80% of cases, primary hyperparathyroidism is due to a single benign tumor known as a parathyroid adenoma. Most of the remainder are due to several of these adenomas. Very rarely it may be due to parathyroid cancer. Secondary hyperparathyroidism typically occurs due to vitamin D deficiency, chronic kidney disease, or other causes of low blood calcium. The diagnosis of primary hyperparathyroidism is made by finding elevated calcium and PTH in the blood.Primary hyperparathyroidism may only be cured by removing the adenoma or overactive parathyroid glands. In those without symptoms, mildly increased blood calcium levels, normal kidneys, and normal bone density monitoring may be all that is required. The medication cinacalcet may also be used to decrease PTH levels in those unable to have surgery although it is not a cure.