The Regulating Ability of Hormones

Your bloodstream must keep its level of electrolytes, such as calcium, within a narrow range to keep your body functioning. But the amount of electrolytes you consume can vary from day to day. How does your body keep a stable amount in circulation?

A healthy human body regulates the level of electrolytes by manufacturing, storing, and releasing hormones into the bloodstream. Hormones are chemicals that coordinate various functions of the body. Even a tiny amount of a hormone can dramatically influence your body. The Encyclopedia Britannica states that the release of hormones is “not a haphazard process; it is subject to precise, intricate control.”

For example, the parathyroid glands in the neck detect tiny changes in the amount of calcium in the blood. These glands—normally four in number—are each about the size of a grain of rice.

When these glands sense that the calcium level has dropped below a certain level, they quickly release a hormone, potentially within seconds, that signals your bones to release stored calcium into the blood. This hormone also stimulates your kidneys to stop filtering calcium from the blood and your small intestine to increase the amount of calcium it absorbs from food.

However, if the blood contains too much calcium, the thyroid—a separate gland—releases a different hormone. This hormone signals the bones to absorb and store more calcium and stimulates the kidneys to filter and eliminate more calcium than usual.

These hormones are just two of more than a hundred that the human body uses to adjust or regulate various processes.

What do you think? Did the regulating ability of your hormones evolve? Or was it designed?