The human body is an exquisite machine, partly because it maintains functionality in a variety of environments. Humans can thrive in conditions ranging from the arctic to the equator, and with a variety of diets and lifestyles. Part of the reason for this adaptability is the body's ability to maintain homeostasis.
Homeostasis is a fancy word meaning "equilibrium," and it entails many interwoven variables that are amazing to consider. Temperature is among the most straightforward of these. The body sweats to keep cool and shivers to stay warm. But the human body is masterful at balancing many other factors. Most are subtler, involving the regulation of hormones and other bodily chemicals. All of the body's systems self-regulate using an intricate coordination of three principle roles: signal reception, centralised control and action.
All of the body's systems work together to maintain balance in the body, but various systems do have specific roles. Two of the most important systems for maintaining homeostasis are the nervous and endocrine systems. Basic bodily functions such as heart rate and breathing may be stimulated or slowed under neural control. The nervous system helps regulate breathing and the urinary and digestive systems, and it interacts with the endocrine system. For example, part of the brain triggers the pituitary gland to release metabolic hormones in response to changing caloric demands. Hormones also help adjust the body's balance of fluids and electrolytes, among other key roles in all the body's systems. Less energetically expensive, but no less important, roles in the maintenance of homeostasis include the lymphatic system's ability to fight infection, the respiratory system's maintenance of oxygen and proper pH levels, and the urinary system's removal of toxins from the blood.
The human body fends off many challenges to its maintenance of balance. A diet that lacks the right nutrients in the right amounts will induce the body to compensate or become sick. Exposure to drugs, alcohol and other toxins kick the excretory functions into high gear, lest these substances accumulate and damage the body's cells. Stress and depression can challenge the respiratory, cardiovascular and endocrine systems, and thereby weaken their respective abilities to maintain homeostasis. And insufficient sleep can work all of the body's systems too hard, impairing the body's balance. So, while the human body is an amazing entity with exquisite abilities to counterbalance insults, healthy lifestyles and choices can go a long way to help.