schematic of endocrine system
Dysfunction of endocrine tissues and organs can cause an inordinate amount of problems that belie their small size. Dedicated endocrine organs (thyroid, adrenals, pineal, pituitary and hypothalamus) weigh 50 grams (roughly 2 ounces) and the endocrine component of other organs (ovaries, testes, pancreas) add about another 50 grams (see schematic on right).*
*Easily 15-fold heavier than the average Kardashian brain.
The bulk of endocrinology practice is caused by acquired disease, in particular type 2 diabetes*, which is increasing exponentially in developing countries to the point of being called a 21st century epidemic. In 2010, an estimated 9% of the world’s population (415 million) had diabetes, a number expected to increase to 642 million by 2020, with the bulk of that increase occurring in low- to middle income countries.
*A condition due to altered response to insulin which is produced in the (pancreatic) islets of Langerhans, at 12 o’clock, bottom image. Also, see entries for exenatide, maturity onset diabetes of the young
islet of Langerhans (at 12 o’clock)
The surge in global diabetes mellitus has been attributed to an increase in sedentary lifestyle, higher consumption of carbohydrates and saturated fats, overlying a substrate of malnutrition and genetic predisposition. Preventing and controlling diabetes is particularly important, given the high cost of its complications: blindness, end-stage renal disease, vascular disease leading to amputations, diabetic coma and early death.
Endocrinologists in North America are board-certified in the field after three years of internal medicine and a two or more year fellowship in endocrinology. In the UK, the post-medical school training consists of two so-called foundation years, two years of core medical training, followed by 5 years of higher specialty training (for a total of 9 years after medical school). In addition to diabetes, endocrinopathies include hypothyroidism (see central hypothyroidism), metabolic bone disease related to calcium homeostasis and osteoporosis, reproductive disorders—which are typically managed in the subspecialty of reproductive endocrinology, most of whom are trained in obstetrics, and an array of growth-related disorders in children—which are typically referred to a pediatric endocrinologist. Overweight/obesity disorder, formerly the domain of endocrinology, is now usually treated by bariatricians (bariatric physicians).