What Do My Kidneys Do?
The answer is, quite a lot! The kidneys, which are part of the urinary system, are two bean-shaped organs, each about five inches long and three inches wide – about the size of a fist. They are located just below the rib cage, one on each side of the spine. The kidneys play an important role in keeping the body functioning properly. Some of their important jobs include making hormones that help control your blood pressure; making red blood cells; and keeping your bones strong and healthy.
Perhaps the kidneys’ most important job, though, is to filter your blood and help get rid of waste products from your body. As blood flows past cells and through tissues, it collects more than a hundred different types of waste, as well as any excess sodium, blood sugar, and water in the body. Carrying all these waste products, the blood then travels to the two kidneys, where the wastes and excess substances are made into a liquid called urine. The urine passes through two tubes called ureters, one extending from each kidney, until it reaches a kind of “storage bag,” called the bladder. From there the urine leaves the body.
The average person has one to one and a half gallons of blood circulating through his or her body. The kidneys filter that blood about forty times a day!
Filter System
The blood vessels entering your kidneys divide into smaller and smaller branches. These lead to tiny filtering units called nephrons , which are so small that you can only see them with a high-powered microscope. There are more than one million nephrons inside each kidney! Tiny as they are, these nephrons catch all the stuff your body doesn’t need, and they send it all out as waste.
Food for Thought
The kidney bean is named for its resemblance in both shape and color to a kidney.
Facts & Figures
Although the weight of the kidneys is less than 0.5 percent of the total body weight, they actually receive a lot more blood than the other organs in the body. Almost 25 percent of the blood pumped by the heart goes to the kidneys!
The Great Balancing Act
Another important function the kidneys perform is monitoring the amount of fluid in the body. If someone does not drink enough, and/or loses fluid through sweating, his blood contains less fluid than normal. When this blood passes through a certain part of the brain, special receptors detect the drop in water level, and the pituitary gland (housed in the brain) is stimulated to release a special hormone into the blood. When this hormone reaches the kidneys, it causes these wonder organs to increase the amount of water they absorb from the liquid they are filtering. Thus, more water is retained, and less water is sent out through waste.
Similarly, if someone drinks a lot of water, this extra fluid finds its way into the person’s bloodstream, and tells the brain receptors of the increased water level. This, in turn, informs the pituitary gland to release less of the special hormone. When the kidneys receive this message, they re-absorb less fluid back into the system, and more water is sent out through waste.
It’s pretty incredible that each little kidney, weighing just six ounces, is so complex and so advanced that some of its functions are beyond human comprehension. Surely, whatever we do know about the kidneys is enough to make us recognize the greatness and wisdom of the One Who created them.
What Are Kidney Stones?
If you ever heard someone complain that he was in pain because he had kidney stones, you probably wondered: What exactly are kidney stones, and how do they get inside the body?
Kidney stones are hard collections of minerals and salts that form inside the kidneys when too much of certain minerals, such as calcium, oxalate, and phosphorus, accumulate in the urine. These minerals are normally found in urine and do not cause problems. However, under certain conditions, these minerals can become too concentrated, and then they separate out as crystals. When these crystals in the urine attach to one another, they accumulate into a small mass, or stone. That is called a kidney stone.
Kidney stones vary in size. They can be small, like a tiny pebble, or they can be a few inches wide, or even bigger.
Most kidney stones pass out of the body on their own, without causing any harm. The smaller the kidney stone, the more likely it will pass by itself. If a stone is too large to pass on its own, several treatment options are available. Pain medicine and plenty of fluids help most people with kidney stones get better.
Staying Hydrated
Kidney stones often have no definite, single cause, although several factors may increase the risk of them. The leading cause of kidney stones is a lack of water. Kidney stones are more commonly found in people who drink less than the recommended eight to ten glasses of water a day. When you aren’t well hydrated, your urine becomes more concentrated, with higher levels of certain minerals, and when mineral levels are higher, it’s more likely that a kidney stone will form.
A Busy Bean
Kidneys pump around 400 gallons of recycled blood every day!
Fact or Fiction??
Drinking milk causes kidney stones.
This is not true. Drinking milk, which contains calcium, does not cause painful kidney stones to form. As a matter of fact, some research suggests that drinking milk is associated with loweringone’s chances of having kidney stones. According to this research, it is not too much calcium that can cause trouble, but having too little of it.